I still like my handy little Creative Labs Prodikeys. It's a toy for sure but a useful one. Lists for $99 but can be found cheaper. Comes with Sound Blaster Live! soundcard.
http://www.prodikeys.com/

Oh BTW: it comes with some arranger software! Don't get too excited - the software is for kids.

[This message has been edited by The Pro (edited 08-20-2003).]