There's this brand called Ultrafire. They pretty much make copies of Surefire at cheaper prices, but quality is good.

I have this one and it's great. It uses a single AA, cree led p4, bright and long lasting.
http://www.newexcite.com/shop/index...o&cPath=7&products_id=96

This one is similar but comes with an extended tube to fit 2 AA.
http://www.newexcite.com/shop/index.php?main_page=product_info&cPath=3&products_id=9

Each cost less then $25 shipped. Full reviews here: http://www.knifeforums.com/forums/showtopic.php?tid/801591/tp/1/