Cyclocross - Converting a Road Bike?

I'm shopping around for a new roadie...had planned on converting my existing road bike to a fixed gear, but started contemplating what I could possibly do to it to make it somewhat like a cx (knowing...or at least assuming...that based on the frame geometry and cable housing setup, it'd never be a 'true' cx).

It's a Trek 2200 ('01), alum frame/carbon fork. I guess I could simply slap on some cx tires and be done with it? Anything else worth considering?

The big question is how much tire you can fit between the stays. Measure, eyeball, test before getting too far into that program. Expect to have to let air out of the tires to get the wheels on / off the bike.

That's about it.

if you are not looking to race, but want to do some light trails and fireroads, a 650b comversion could give you more clearance