Quake 3 for free and easy online play, in a semi-legal way:

 STEP 1: 
Download http://www.google.com/search?q=%2Bpak0.pk3+intitle:index+%2B457M
and then place it in X:\Quake3\baseq3\
 
 STEP 2: 
Download http://www.planetquake4.net/download.php?op=fileid&lid=1150 and
install to X:\Quake3\

 STEP 3:
Get latest CPMA from http://www.challenge-tv.com/index.php?mode=filedetail&file=106
Get CPMA Mappack(CPMA requires it) from http://www.challenge-tv.com/index.php?mode=filedetail&file=185
CPMA client goes in X:\Quake3\cpma\ - map pk3's go in X:\Quake3\baseq3\.

 STEP 4:
Make a shortcut for CPMA pointing to "X:\Quake3\quake3.exe +set fs_game cpma"

 STEP 3:
Play! If you need a cd key for any servers with sv_strictauth 1, here are a few, not all may work anymore:

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You're welcome, and PLAY MORE PROMODE!