I've got a few home builds I built over the past 16 months that I'll have at SELEM. A couple will be covered in detail at a "glow in the dark" talk (assuming there is sufficient interest in an update of that talk from last SELEM X), but I'll have at least one "regular" projector that I can do a quick walk-through while stuffing doughnuts down my pie-hole.
Adam B: I think the "cars and coffee" refers to the Seinfeld HBO show called "Comedians in Cars Getting Coffee". Its an enjoyable watch.
-David
<Edit> Oh, and I'd love to see other folks builds to see what ideas I can . . appropriate . . for future builds.