I want to. A friend is using them pretty regularly with great results. Leica is now promoting the IR sensitivity of their M8 for IR photography (Why fit the camera, make people shoot IR. HA!)
I think the new Nikon D40x would be a great camera to modify 'cause it shoots 10mp, and is cheap.
I had a Nikon D100 converted at IR Digital a few years ago. I like the results. You can check my Verdun Infrared or Battle of Actium galleries for typical images. The conversion cost was under $300, as I recall. It works best for me with my old AI manual, fixed focus lenses. Zoom lenses seem to have more focus problems, so need small apertures -- f11 or smaller. Hand held works fine in most situations. Using an IR filter on a non-converted camera often means using a tripod to get good results.