is there a good muscle system for XSI?
(free or comercial)
…Muscle System?
i believe theres a commercial one(like, duh…)
ok that’s great, now can one of you help me find it?
just a quick look, might this be it:
http://www.xsibase.com/tools/plugins.php?detail=1168 (edit: that ones dead link there :()
im sure theres more, why not look for your self more from xsibase.com? 
Google, Wikipedia, and Ebay are your best sources.