Talking of old products.... I dug this one up out of storage the other day along with the manual & songbook:
I remember was a PITA to get it working properly, but when it did work it was great. Basically you give it a MIDI file, decide which part you want to play, and it plays all the other parts to the same tempo as you are playing.
In practice however, it relied on you playing enough notes for it to reliably detect your tempo. For one song I ended up writing a silent part that involved playing constant 1/8 notes for it to keep regular time.
I seriously doubt if BandLab would consider resurrecting this one (and I'm not suggest it either), but it was a cool bit of Cakewalk history.
M.