I was thinking of having a custom titanium frame made by xacd. I've always wanted a bike made of titanium, and they're really cheap. They'll also build to whatever specifications they're given.

After a bit of contemplation, I came up with an insane idea that probably makes no sense. I like track bike geometry. What I don't like is being restricted to skinny tires. I want the ability to run the fattest tires that could possibly exist. So what I'd really like some kind of track/CX hybrid that has clearance for 29" tires.

Is something like that even possible? would it operate like crap? any thoughts? I don't know a lot about fitting/geometry; I'm used to picking up whatever frame I can find and using it, so I haven't looked at these considerations before.