Thanks!

Harrkey, I'm not uncomfortable using these old beasts as handwarmers while hunting or camping. I'd be uneasy using one in a tent, because even though they're "catalytic" heaters they need to be ignited with a flame and then "burn off" for a while. Never had an air-tight tent, so I doubt they'd generate dangerous levels of CO. However, my experience putting them in the foot of a sleeping bag (years ago) is that they quickly fail and cool off (perhaps because they do need SOME air).
Also note, I've had several of them leak or leach Zippo fuel: anyone who's had an over-filled or leaking fuel lighter in a pocket can remember the burn!

Have had no experience with the solid fuel types.

Several folks have attested to good results using the Charcoal sticj hand warners. See this web page for an example.

I've used the chemical hand/foot warmers, they have the added advantage of being thin enough to wear in your mits or boots and last all day or night long. The Reusable ones are great for a burst of heat, as in slipping into a cold sleeping bag ...

But the best one is the charcoal burner mentionned. I've had them for years and they are bomb proof. You do need the charcoal refills !!! though and they might be hard to light up with frozen fingers, so don't wait too long before pulling them out !!!

How about one with pink polka dots? Grrr (making manly sounds)

Like ironraven's signature says: Teach a man to light a fire, he'll be warm for a night; light him on fire, and he'll be warm for life. <img src="/images/graemlins/laugh.gif" alt="" />