I do something simular with wavetables in the spirit of PPG or Waldorf synthesizers (stepping through a bunch of single cycle waves), its great in combination with the moog~ filter and it sounded well on a concert yesterday. There are two windows applications out there which can generate wavetables and I managed to run them on my Linuxbox with Wine. Its the freeware Tranzilon
http://www.xs4all.nl/~avg/tranzilon/info.html
and the shareware wave256 http://www.sonicspot.com/wave256/wave256.html
Opensource solutions would be cool but I dont know any, I guess a pd patch should be possible and I tried something in csound some years ago.
Cheers,
Malte