Forum
Have just discovered this site via ConceptArt.org and have found it hugely handy, due to the fact I can no longer get along to a regular life drawing class (oh how I miss thee, Queensland Animators).
http://www.posemaniacs.com/pose/thirtysecond.html
Comes in several times, with an advanced mode.
That site is very cool, but I wouldn't consider it a substitute for life drawing