I just got a pair of powerlet heated glove liners in the mail... and a heads up that these are currently on sale for only $55CDN plus tax and $18 shipping (very fast shipping too through Purolator).
http://www.powerletcanada.com/heated_clothing
These things work awesome. I tried them out for the first time today and on level 3 out of 5 my hands were very warm. I wore them inside some Olympia Goretex overgloves.
These gloves also use FIR, but in my experience are many many times warmer than the Firedupx battery operated heated gloves. I barely feel the heat in those (especially the broken one ;-) )... these liners, on-the-other-hand are the real deal. I'm not sure how I rode in cold weather before without them.