Similar to the Thanko USB Warmer Mouse, this Brando mouse keeps your hand warm with USB power. The mouse gets up to about 45 degrees C, which is about 113 F, which means it actually gets pretty hot.
This mouse is $22, compared to the Thanko's $25, so I'm totally getting one right now. My hands are always so freezing, it's a wonder I can typasdfjlzxvcio.
Product Page [Brando]