Connect to wifi at boot

Like all good nerds, I have needs for computers in several places around the house, but I have little desire to run cat5 cables all over the place to provide internet connectivity. That's what wifi is for. In most Linux distributions, though, the wifi connection is dependent on the user login and storing the keys in the users keyring. Consequently, there is no internet access via wifi until after the user logs in. With some simple configuration, though, it is possible to connect to wifi on startup and have that connection available even if the user has not yet logged in.