Not going to get into specifics but here are two reall intersting threads regarding yamahas ez-eg learners guitar forget the fact that its a kids toy and lets you play along to pre programmed songs. It also sends midi!!! And can be found for US$150 odd.
http://www.kvraudio.com/forum/viewtopic.php?t=41787
also a pretty simple vid of a guy using it to run a soft synth:
http://www.youtube.com/watch?v=ra8pUEYYU0w
currently written midi editing suite for it is Windows only.
Enjoy trawling through all 75 odd pages!
