http://project-vortex.com/

Q2 mod that adds RPG elements. Has pvp modes (ctf, domination, and pvp) and pvm (invasion maps and regular maps with random monster spawns), bosses (in pvp). Has mage, necromancer, vampire, engineer, cleric, shaman, knight, poltergiest (shape-shifter), soldier, and alien classes with class abilities (fireballs to napalm grenades to auras, etc.) and general abilities (vitality, str, ammo and power-cube (mana) regen, etc.) and class specific talents (from lvls 10 and onward) and upgradeable weapons. You can equip yourself with 'runes' which enhance either weapon or ability scores or both.
Pretty fun and pretty free, so a win-win. Server requires anticheat (http://antiche.at/), site has a helpful and active forum, and you should play.
DL is on the main page.

i am going to dust off my copy of Q2 and try this out

Sweet deal.
You don't even have to dust it off, the dl on the site is an installer that has Q2 3.20 and all the vortex files and r1q2 client.

q2 was the last fps I played until resistence fall of man.

people still play it. thats why i love PC gaming. some communities are really devoted.