Ditto on the small bottle of alcohol - Although sometimes I like the gel and have been known to take a small bottle of purell - since I carry an alcohol stove using a little as hand sanitizer is fine.

I don't *wash* hands with it - I use good old water and sand/rocks/whatever for that. The only time I use it is upon leaving the toilet area after a poop. Not eating your own or someone else's feces is usually a lot more important in preventing gastrointestinal upset
on the trail than treating your water.