I have 12" PB and today when I was at school, I was using the wifi as usual, and then I had lecture and I lost my wifi. but heres the weird thing. everyone else using PC laptops had wifi. I noticed someoen else iwth a 12" pb and asked him if his wifi was working and he said now. so I ask, whats the difference with this "airport extreme" thats different than the wifi cards on pc laptops that made me suffer through my boring lecture today?