Upload & Sell: Off
There is a certain place where an old camera is no longer functional, and for everyone it is a different place. For me, the 1D2 and 20D were the turning point. I think there is a bigger difference between the 10D and 20D, than between 20D and the 50D.
I love my 1D2, even with the small screen, lack of joystick, not having the RAW/JPG split for backup, etc. The 1D, however, is just too old to be practical. The 40D is a fine camera, I used one for about two years.
If you can fine a 1D2 get it, if not then get the 40D. I take it back, save for a few more months and get the 1D2 anyway!