This is an interesting thread. I hadn't considered the idea of the ideal companion phone before, but the premise is sound. You don't need duplication of features, just broad and robust support for the N800's strengths. So... in the ideal companion phone, you don't sweat a small LCD, lack of multimedia, etc. You essentially need the fastest broadband, built-in GPS, bluetooth, etc. I would also suggest it allow easy creation of PANs for multiple N800s.

Hmmm. This idea needs to be elevated.