Found a couple vids,

http://www.youtube.com/watch?v=Usdzh...eature=related

http://www.youtube.com/watch?v=YCz41Dzt6wU

The first one just uses a water bottle, which could be carried in a cage for easy access. I wonder if the right water bottle(s) would squirt farther than most others. There were some lab bottles that someone recommended for long-distance squirting. Wow. I like this idea. Much simpler than a squirt gun or mister bottle. Fewer moving parts, less chance of failure or need to replace. Plus it fits right in, on a bike. Great.

Now, who makes those bottles?

(Could also make this idea even more effective by doing grip exercises to strengthen the appropriate muscles in the hand and forearm. Great. Very human powered.)