Personally, I like the magicshine /u/asssboy recommended, but I've also had good luck with models similar to this one: http://www.amazon.com/SecurityIng%C2%AE-1200Lm-Diving-Flashlight-Meters/dp/B0098HRSOM/ref=sr_1_16?s=outdoor-recreation&ie=UTF8&qid=1429757436&sr=1-16

Look for lights using CREE LEDs. Lots of lumens for little cost.