Here's something fun. I used my BK-7m and an old Yamaha KX5 keytar, recorded using the MP3 recorder, so no editing at all.
The idea is, can you input the chords AND do the solo all with just one hand?
The trick is to use the Pianostyle mode, so that the arranger doesn't change chords until it sees THREE notes. So you can still solo with up to two, and not drive the chord recognition crazy!
Now, please be aware that this was a very hastily put together demo, and no editing was possible (nothing to stop you doing this into a sequencer and polishing it, but that wasn't what I was going for, here), so you can hear the odd spot that I don't quite get it right. But with practice, you can get pretty good...
Once again, I emphasize, this is NOT an SMF or MP3 backing. It's all played live. Just goes to show, even ONE hand can do some pretty amazing stuff on an arranger!