Recently I faced a weird problem at home with my WiFi. Whenever I turned my laptop on, running Ubuntu 13.04, everything else (wireless-wise) stopped working. I tried everything, but with no success. Pretty much only my wife’s laptop was still able to browse the net, but everything else was “dead in the water”: the iPad, our mobiles and our visiting friends’.
Luckly enough, I came across this post that helped me solve the issue, which pretty much sums up to this:
sudo modprobe -r wl && sudo modprobe brcmsmac
Hope this helps someone.