That thing where you connect the two machines together with an ethernet lead might work, if you can figure out how to do it - I seem to remember we had a dicussion over at 68k once where it was said that a Windows PC connected to the internet via WiFi could pass the connection across to a Mac in this way, so I assume it will work between two computers of any sort and using any sort of internet connection. However, I could never got it to work and just bought a wireless bridge instead, which is much better anyway.