This one's been around the block a time or two, but sadly, it still won't be available for use as an in-law stocking stuffer. Black & Decker's $39.99 TLD100 Thermal Leak Detector packs an infrared sensor that can detect where cool air is being let in around older windows, doors, etc. You simply aim it at a suspect area on your wall or molding, set the threshold for temperature change and comprehend the readout on the LCD screen. Too bad this will be way less useful when it launches in the Spring, but Old Man Winter's never too far out.

[Via Coolest Gadgets]