DNJ, mostly as straight keyboards (solo or in bands) but there are 1 or 2 using it as an arranger keyboard and midi file player. An example of a straight keyboard use might be ddas moderator of the NI Forum:
http://www.daviddas.com/index2.html

There is another guy I think his name is Bruce Richardson on the Northern Sound Source forum who uses computers/GigaStudio for live performances.

mhenningson, from the Brainspawn Forum is another person who uses this approach.

There are others but do not remember their names.

[This message has been edited by Frank L. Rosenthal (edited 08-30-2003).]