I just picked up the SteriPEN Protector Handheld Water Purifier for $49.27 with free two-day shipping (w/ Amazon Prime). Seems like a good deal as it's going for $100 most places (Moosejaw, Campsaver, Rock/Creek, ect).
SPECIFICATIONS of the Protector by SteriPen
•Product Dimensions: 6.1 L x 1.5 W x 1.0 H in.
•Product Weight: W/O Batteries: 2.3 oz
•Product Weight: Batteries: 3.6 oz
•Battery Type: CR123 (2)