Yugster offers the Night Ize Inova X2 LED Flashlight for $14.97. Coupon code "FACEBUCK" drops it to $13.97. With free shipping, that's the lowest total price we could find by $24. It's made from aluminum, is water-resistant, and requires two AA batteries (not included).
Note: The countdown timer on the product page does not reflect an actual expiration time and resets daily.