Extensible auto-complete tool built on Prototype and Scriptaculous
It handles the basics of displaying a text field which has an auto-complete dropdown. What happens then is up to you.
Easily extendable by passing in overrides in the config, or sub-classing to provide your own functionality.
Take a look at the examples for ideas of what you can do with it.
doesn't care what kind of data you have, arrays, hashes etc…
populate the data with Ajax, local data, select boxes, anything
allow single or multiple selections
basically whatever you want it to do
View the demos -> rlivsey.github.com/multicomplete/examples/