Crave

For just $9.99 you can stuff a stocking with the cool, practical HiJack Headphone Splitter Keychain.

(Credit: ThinkGeek)

What do you get for the iPhone user who has, well, an iPhone? After all, the device itself is the gift that keeps on giving. Am I right?

Anyway, I've rounded up five iPhone-friendly items for the holidays. Whether you're shopping for a Secret Santa gift for a co-worker, a stocking stuffer for your hubby (or missus), or something to round out the latter nights of Hanukkah, one of these should fit the bill.

1) A gift card...that later turns into an iPhone stand! Start with any gift card--Starbucks, iTunes (duh), or whatever--then tell the recipient to bring it back to you after it's used up. Following these simple Instructables instructions, do a little waving-your-magic-wand thing and turn that card into a cute, clever, portable, and virtually indestructible stand. Who knew a gift card could keep on giving?

2) The world's best (?) battery pack Blogger Josh Bancroft calls this Monoprice iPhone Backup Battery Pack the "best $15 you can spend," and I'm inclined to agree. For just $15.23 you get a 2200mAh battery, which is good for roughly two full iPhone charges. Just one problem: It's currently on back order. Well, you can always print a photo from the product page, write "coming soon," and stuff that in the stocking.

Amazon has announced small enhancements to certain Kindle models.

(Credit: Amazon)

Just in time for the holidays and facing heavy competition from Barnes & Noble's upcoming Nook e-book reader, Amazon has announced that it has improved the Kindle's battery life when the wireless connection is turned on and will now be offering native PDF support for its e-book reader. Both the battery-life boost and native PDF support will be available to owners of new Kindles and some older models via a firmware upgrade.

In a press release, Amazon says the Kindle now has battery life of up to seven days with wireless turned on compared with four days previously. However, battery life with wireless turned off remains the same (around two weeks).

"Battery power management for portable wireless devices is a complex technical area, and the battery life improvement announced today is the result of a six-month firmware improvement and testing program," the release notes.

As for the native PDF support, Amazon says you can now "read professional and personal documents in their original PDF format without conversion." To read PDF files, you either e-mail them to your Kindle e-mail address or move them over using a USB connection. If you prefer to have your PDF documents converted to the Kindle format, you type "Convert" in the subject of the e-mail when sending documents to your "@kindle.com" address.

All new Kindles will ship with the battery-life improvements and native PDF support in place, but if you bought an earlier Kindle you may be eligible for both enhancements via a firmware upgrade that will automatically download to your Kindle when you turn its wireless connection on.

We're still trying to determine which models will get the upgrade (we have an e-mail into Amazon's PR team). In the meantime, if you have an older Kindle 2 or the original Kindle, let us know if you got the upgrade.

Comments?

Update 12:30 p.m. PST: We have confirmed with Amazon that the latest Kindle, released in October, as well as the Kindle with U.S. wireless (released in February) now have native PDF support and the improved battery life. However, as suspected, the original Kindle is not eligible for the upgrade.

(Credit: Sanyo)

Sanyo is introducing a portable USB recharger that can power mobile devices, such as the iPhone, that require a higher current for charging.

The Eneloop Stick Booster, part of the same family of power products as the USB Solar Panels, comes with two rechargeable eneloop AA NiMH batteries.

The company says the batteries can be recharged some 1,500 times, and eneloops are more effective than dry cells because they don't meet the current requirement of some devices.

The aluminum-construction Stick Booster weighs 2.6 ounces and is 5.8 inches long. When switched on, it can provide power for about 90 minutes on two fully charged eneloop AA batteries.

The device goes on sale December 1 in Japan for what appears to be about $35.

(Via Akihabara News)

We purposely attempted common jumper cable errors with the PowerSafe cables and lived to tell the tale.

(Credit: Antuan Goodwin/CNET)

I was given my first set of jumper cables at the same time I received my first car. Before setting me loose on the world, my father gave me a very serious speech about the dangers of improperly jump-starting a vehicle. I was warned of potential electrocution, sparks igniting gasoline fires, and--most seriously--acid spewing battery explosions if the cables weren't connected in just the right way and in just the right order. Even armed with this sacred knowledge, I still throw sparks every time I jump-start a car, just for kicks. Sorry, dad.

However, most drivers didn't get my dad's speech and as a result, they find themselves in an even more precarious situation when the day comes that they need to borrow a few electrons to jump a dead battery. Here's where Energy Safe Technologies come in with its PowerSafe jumper cables.

The PowerSafe jumper cables look like your standard jumpers, with a pair of terminal clamps on each end. However, midway through the cables' length is a small electronic brain that monitors the state of the connections and only lets power flow when everything is hooked up just right.

So, if you accidentally connect your cable backward on either end, the system will display a red warning light and the power stays off. If you accidentally touch the loose ends of a live cable, the red light glows and there are no sparks. If there's a short of any kind, even within the dead battery, the red light glows and everyone remains safe.

Once both ends are properly connected and both indicator lights glow green, the system uses a soft start circuit to gradually ramp up the power flow, eliminating power spikes and protecting delicate vehicle electronics.

We were given a demo of the PowerSafe cables prototype at Energy Safe Technologies' booth, tucked away in the back of the SEMA Show's north hall. No matter how haphazardly we connected or disconnected the cables, we were unable to cause a fire, throw wicked sparks, or create an acid-spewing battery explosion--which is boring, but very safe.

The PowerSafe jumper cables should be available in early 2010. Pricing has not yet been announced.

(Credit: CNET)

CNET Labs finished their panel of battery drain tests for the fifth-generation Apple iPod Nano, and the results are better than expected. Testing for continuous playback of audio and video, the Nano reached an average of 33.6 hours of audio or 5.3 hours of video.

Given Apple's own modest battery rating of 24 hours of audio or 5 hours of video, we expect Nano owners will be happy to know they have a little extra time to squeeze from their iPods.

It's not very glamorous, but this battery pack delivers iPhone power on the cheap.

(Credit: Meritline)

The older your iPhone gets, the worse its battery performs. Don't blame Apple: it's just the nature of rechargeable batteries that they wear out over time.

Sadly, you can't just swap in a new one--not without some warranty-voiding surgery. But you can plug in external power, which is cheap, easy, and affordable.

For example, Meritline has an 1800mAh iPhone backup battery for $9.99 shipped. That's after applying coupon code MLC262531102717A (which expires Oct. 29) at checkout.

The standard iPhone 3G battery has an 1150mAh capacity, meaning this plug-in pack should afford at least 50 percent more runtime all by itself. You can use it for emergency power if your battery's on empty or to recharge your iPhone on the go.

And, hey, 10 bucks? Grab a couple. Throw one in the glove box, another in your coat pocket, etc. That way you'll always have backup power when you need it.

This battery pack is compatible with all iPhone and iPod Touch models. Keep in mind that because it ships from Hong Kong, it could take a couple weeks to reach your mailbox.

(Credit: University of Missouri)

Scientists at the University of Missouri are developing a small nuclear battery that they say can hold a million times more charge than standard batteries.

The radioisotope battery, being developed by Jae Kwon of the Department of Electrical and Computer Engineering and other researchers, is the size and thickness of a penny.

That makes it smaller than nuclear batteries used in space and military applications. Kwon says it might shrink to less than the thickness of a human hair if the right materials are used.

The battery is designed to drive micro/nanoelectromechanical systems (M/NEMS). Such devices include labs on a chip, and biological and chemical sensors.

The nuclear battery produces power from charged particles released by radioactive decay. It also uses a liquid semiconductor material, rather than a solid one, to minimize damage to the battery.

Kwon said the technology is safe. "Nuclear power sources have already been safely powering a variety of devices, such as pacemakers, space satellites and underwater systems," he noted.

The team has applied for a provisional patent on the battery.

(Credit: Columbia)

These boots will keep your feet extra warm, as they use built-in rechargeable batteries to heat them up for four to eight hours straight.

The Columbia Bugathermo boots will make your feet straight-up hot even in the coldest of conditions, at least for a few hours. You'll want to start heading home when the battery display starts dropping, lest you're stuck out in the snow with just plain normal boots on instead of futuristic superboots. You wouldn't want that to happen!

The boots combine an integrated toe heating element and underfoot insulation and have three temperature settings. They're available now for $250.

This story originally appeared on Gizmodo.