I'm trying to build an autocompletion thingy that suggests categories
based on user input using the opensearch API [1].
I also did something similar for our wm-metrics [1], ended up with some jqueryUI + cutting the prefix with a callback method [2] (I am JS-0.5 ;-)
[1] http://tools.wmflabs.org/wm-metrics/ [2] https://github.com/Commonists/wm_metrics/blob/master/app/static/commons-sear...
Hope that helps,