If you are hosting a game of Quake 3 (does not work in Quake 1 or 2 - thanks Ads) — and you're a dirty rotten cheater (or maybe not) — you may change the value of the almighty Quad Damage, making it barely-mighty or stupidly-excessively-TrustMeOnThisOneDoNotUseABfg10k-almighty.
Bring down the console with the ~ key. Type "\g_quadfactor" (sans quotes) to display the current Quad Factor - by default, 3.
Now give it "\g_quadfactor x", where x is your current favorite number. Examples include: quadfactor 0 turns Quad bearers into temporary pacifists, 1 makes Quad Damage have NO effect (except the player still glows blue), 4 brings the Quad Damage in line with Quake 1 & 2 (and mathematics). Or, you could try 3.5 to put it halfway. Negative values are treated as 0. Those Arena Masters want blood, it seems.
To really piss people off, \bind this to a couple of keys, like so:
"\bind [ g_quadfactor 0"
"\bind ] g_quadfactor 12"
Now you can use [ to make Quad worse than useless (when an enemy picks it up) and ] to bring it to 12x damage (when your team gets it). Play with those commands if you want to customize this feature, it won't hurt you. Keep in mind that each time the Quad factor is changed, all clients are informed about it, and they probably won't like it. So keep it up, and you'll be playing solo before you know it! Minutes of fun!
Oh and one more thing, big Quads give big knockbacks! Big knockbacks give...interesting rocket jumps!