I only need to connect to 2 other PCs besides my 2 indoors within 25m but through 2 walls... my 2 will be wired. I did think of just linking my two with a crossover cable and nics, but that would mean I'd have to be running the TBred for the TBird to access my broadband and since I have it dual booted with Linux I don't think I'd be able to surf with Linux then.
Initially I'll just have my 2 wired in and I'll extend it to the other 2 on wireless lan later, but at that price I can afford to get it now - when I get back from holiday - rather than wait till late January, which is what I'd intended and set up the wireless lan part of it then instead.
The mini-itx I'm planning to build is intended to give me access to streaming media from the net through my TV - allowing me to view concerts and events I wouldn't otherwise get in real time not 6 months later.