QA Worldwide CP9005 Cable Clamp Cable Organizer
A must-have!
These clamps are awesome.  I like the small ones the best because I mostly have small power cords that I want to bundle up (like on kitchen appliances and various chargers).  I used to always use zip ties and the velcro ties but these are a million times better.  They are easy to use, they hold the cords tight and you can reuse them over and over.  I have never broken one of these clamps and I use them constantly so they appear to be pretty durable.  I've used the same clamps for at least a couple of years.  They are hard to find in stores (especially the small ones).  But now that I found them here I plan on stocking up!