Awhile back, a package arrived at my desk containing two unassuming little boxes that contained what I presumed on first glance were brushed-metal paperweights. I set them aside to attend to more pressing matters and didn't give them much thought until I was sorting through some drawers a couple weeks ago and one finally made its way out of its compact packaging and onto my desk. I then promptly kicked myself for not using the OXO Good Grips Cord Catch from the moment it arrived.
The Cord Catch is an exceedingly simple device--actually, it is quite similar to a paperweight. A very cleverly designed paperweight. It's made with one task in mind: to keep your USB device cable from slipping behind your desk. Three features--shape, weight, and grip--serve to accomplish this goal. First, a contoured crevice keeps the various USB cables in place. Next, the Cord Catch is heavy enough to not slip off the desk itself, even with several cords "pulling" on it. Finally, you have Good Grips' customary grippy rubber coating the bottom for extra insurance.
It works great, so if you're sick of getting down on your hands and knees to recover crafty cords, consider picking one up on Amazon.com for $7.95. Also, if you keep your computer on your actual desktop (like me) and are slightly OCD (like me), the Cord Catch also does a fine job of keeping cables from cluttering (see below).