To those that give a hoot, I had the AIR frame built up from pillaging my Trek 930 commuter, and a Trek (?) rigid fork.
First off, it requires a really long steer tube. I didn't have anything even close in threaded, so I used the rigid fork from my Privateer buy, which was said to be from a Trek. Just enough steer tube to get about 65% of a CrMo stem onto it. It seems to hold well enough for commuting for now.
Had quite a problem with finding a gearing/chain combo to fit for single speeding, but it's kind of close now without a tensioner. I currently have it geared 34/14, which is a taller gear than I really wanted, but it works for now. When she gets geared for off road, I'll need either an odd-toothed chainring, and/or a tensioner to eliminate chain drop. With 16.56" chainstays, not many combos work without fiddling with worn/unworn chains. But with stays that short, it oughta climb like a frikking mountain goat.
Don't have any pics yet, but will get them up sometime in the near future. It rides really well and handles quite nicely thus far.