All of a sudden the wipers stopped working on my 96 cherokee; radio and turn signals work, wipers do not. Any ideas?

This is probably a failure of either the wiper motor or the wiper function in the multi-function switch. I'm assuming that you have already checked the fuses.

The first step is to see if you can jostle the wiper arms a bit and see if it works (in other words, move the wiper arms back and forth and then try the wipers again). If it works, it's a tell-tale sign of a failing motor. If that doesn't work, next I would try to jump the wiper motor to the battery and see if it runs. If so, I'd start looking at the switch (it's the one in the column with the wiper/turn-signal), if not I'd replace the wiper motor. Either way it's a relatively straightforward replacement.