Linux Users' Groups are also particularly good at getting new people to use Linux. At least, they should be. One of the main problems with Linux is that, to the uninitiated, Linux can be intimidating. A group of users dedicated to promoting open source and The Linux Way who already know lots about setting up Linux helps, particularly since it isn't half as hard to maintain a Linux box as it is to set one up.
At least, thus is the mission of the Clemson Linux Users Group, because we've all been there before...