For the Ubuntu users out there who have recently downloaded Karmic Koala and have inexplicably found yourself unable to connect to any wireless network, with NetworkManager actually graying out the “Enable Wireless” option so that the box remains permanently unclicked, and have spent hours trying to remember your terminal commands to reinstall drivers, etc. downloaded using a mothballed Dell with XP, because by G-d you can’t not use the series of tubes in trying to solve this problem and all the ethernet cables have mysteriously gone missing, help is on the way:
In my case, it was as simple as hitting Fn+F11. The F11 had a little blue wireless networking symbol thereon. Damned power saving feature.