Everyone who rides with me knows my hands and feet are ALWAYS cold. A bad case of frost bite left me with fingers and toes that get cold fast and won't warm back up. I am embarrassed to tell you how many different pairs of gloves I own, much less have owned, in the past 5 years trying to keep them warm. I have tried everything, including lobster gloves with chemical heating packs in the fingers. These gloves are by far the warmest thing I have ever used.
These are heated gloves made by Venture, the name makes me laugh because it reminds me of the cheap department store from years back, but these aren't too cheap. They have a lithium ion battery pack that sits in each glove and is rechargeable in about four hours. Depending on power settings Max, High, Med, and low the battery lasts between 2-10 hours. Having cold hands normally I of course put them right to Max on a ride into the wind 25 degree temps. I was shocked when 15 minutes in my hands were too hot, turned down to high, another 15 minutes still too warm, turned down to medium.... perfect. The reason I think they work so well is that they heat so that the finger tips are the hottest, then cooler as they work down toward your palms, just the opposite of how your fingers are.
They come up high on your arm and have two different adjustment points at the cuff and midpoint. 
One of the better things for me about these is if you do get cold they ramp up hot enough that they'll snap you back to comfortable quickly, that's the benefit of not having to run them on the highest setting to be comfortable. If you have to stop and change a flat on a 20 degree day, you can pop these to max and get comfortable again quickly. They are expensive but when I go through close to 100 of those little chemical warmers in a year, these seem like a much better alternative for the environment. When you add it all up they pay for themselves in two seasons. I'm looking into carrying them at the shop if you are interested drop me an email.
