OT : wireless networking of many laptops

I was having a chat with someone today who asked me if it was possible
to wirelessly network approx 50 - 60 laptops so that they could 'swap'
files at a conference?

The idea is to fit a wireless card to each laptop, which would allow the
users to "wander around the conference centre swapping info with each
other" ... !

The laptops will be a mix of OS, from 98, 2000 to XP

I suggested it would be possible, but a configuration 'nightmare'.

Thoughts?