Some friends of mine bought a speak n say version.  They use it for dj gigs and in their indie rock band. There are pitch shifters, delays, something that makes it auto-repeat, and a volume sensor like on a theremin.   It makes really cool noises, but it is almost uncontrollable.  There's just no telling what will happen at any given time, which is actually fun.  I think they're relatively cheap, too.