This is the second open source application review that I've done, but it really should have been the first. I could probably live without talking to other people (Adium), but I'm not sure I could survive long flights without the occasional movie. Handbrake covers this fundamental human need.
If you're not currently using the open-source Handbrake application, your life is woefully incomplete. Handbrake is one of the applications that you will continue to use when you die. Angels are using it, even as I type, to rip their DVDs to their hard-drives so that they can save battery life on long trips (to Redmond, most likely :-).
Enough gushing. What is Handbrake?
Quite simply, it's a DVD-to-MPEG 4 converter. And what does this mean? It means you can take your DVDs (i.e., DVDs that you own) and instead of carrying them with you on trips, you can simply copy (and compress) them to your hard-drive. Why? Well, so that you don't lose or break DVDs on your travels, but also so that you can preserve battery life. Spinning DVDs in your DVD drive wastes precious battery life. Spinning the hard drive...not so much.
Handbrake couldn't be easier to use, either. Insert DVD. Select the output folder. Go.
Now, you can tweak the settings to improve quality, but I have never found the need to do so, except when converting DVDs for the iPod. Handbrake's default MPEG-4 setting highly compresses a DVD such that you lose quality, but it's more than adequate for normal use. It's only in fast-moving action sequences that I find it creates a little noise. So, for Pride and Prejudice you're golden 100% of the time, but for The Bourne Supremacy, you'll have a few seconds of an imperfect picture.
Any downsides? I honestly can't think of any. It would be nice to have DVD-quality video instead of MPEG-4, but I think the small trade-off in quality is more than worth the benefit that MPEG-4 affords in space. I have much of my home library of DVDs on my laptop, which would be impossible at full DVD file sizes.
This is a must-have application. Let me know how you like it.