midi looping hardware

[Travis Weller <tcweller@purity.com>]

hello,

without getting into the hardware vs. software argument, i'm interested in
finding a hardware (non-computer) solution for overdubbing MIDI events in a
similar way in which the EDP overdubs audio.

the software sequencer i'm currently using (cubase vst on mac) accomplishes
this quite well. set a loop length, start it playing, toggle record
(overdub) on and off as needed. the ability to switch and mute tracks (like
the Alesis MMT-8) would be a big plus. the only catch is: it's on a
computer.

i know from reading this list for a while that many of you use the EDP or
similar overdubbing loop devices. i also know that many of you are MIDI
users. i've seen some good discussions about software vs. hardware
solutions for music creation. so it seems like there would be at least a
few of you who may already be using from something like this.

does anyone know of such a device, or know for sure that one does not 
exist?

thanks,
travis.