The best $10 you'll ever spend. How many times have you had to look behind/around/underneath a rack/mixer/recorder, and you kick yourself for not having your Mini Mag-Lite in easy reach? No excuses when you've got your Princeton Tec Pulsar. It's about the size of a quarter, it fits on your keychain, and it's significantly brighter (no kidding) than a Mini Mag Lite. (Literally only four parts: two pieces of plastic for the case, a high brightness LED, one watch battery.) I carry mine with me ALL THE TIME. One caveat: it doesn't have a "stay on" switch. You need to keep squeezing it to keep it lit. (www.princetontec.com)