Opportunity is missed by most people because it is dressed in overalls and looks like work. - Thomas Edison
im super excited to see where this goes, as i've been researching it alot lately!
I'd start wit Mooseman's setup of a settling tank, from there your filtering options (if you still want more) are pretty open.
I have the grease trap thingy shown above. I don't (yet) have a true filter in it. It does trap globs of crap, tape, etc that was going down the drain before. So it works so far for what we're doing. When I make some time, I'll try to do more with it.