q3test, well.

q3test was id software's innovative open beta programme for quake3arena. q3test used the q3a code, but contained only 3 maps and few models, but all the game mechanics was there. you could download the program and play q3a legally long before it has been released. you were even encouraged to do so, as the player's feedback was one of id software's most important inputs. they constantly updated the q3test and released new versions, improved it, added new models, new effects, changed weapon balancing etc. it somewhat made the development process interactive, and served another purpose: to make the players hungry for more... sure.

so, it was no "sign up for a programme", just download it, playit, enjoy, give feedback, get a new version every couple of weeks, play agin, etc, until it "fits". it's not really been a "beta" version, but a game mechanics test, more like a demo. but not of a finished product.