I was able to rip 3d models from PS2 game Silpheed Lost Planet.
The 3d models were quite tricky, since, instead of storing raw sets of vertices and triangles, it stores what I think it's raw GPU command batches.
I can't release source code yet since the ripper is part of a much larger library I need to polish before releasing... it'll take time... just to let people know
Right now I'm working on another game: Macross for PS2, I've been able to crack down most of the archivers, but found the most interesting meshes are encripted/compressed with a header "CRICMP"... I'm stucked with that one right now... posted a thread in the compressed forum, but no replies so far...