Wow, I didn't expect to see so many old games mentioned here. Timesplitters, RtCW, SoF2...
Timesplitters was awesome. I remember most of all the challenge mission, where you had to fight an army of bustylicious cowgirls with rocketlaunchers. I played that one over and over. I'm sure that left a mark on my impressionable young mind... Besides that, you had a huge roster of hot babes (by PS2 graphics standards) to fill your botmatches with and blow away with knarly weaponry. Nice variety of death/pain sounds, too. No blood in TS1 & 2, but you could decapitate zombie babes. TS: Future Perfect was quite a bit more violent.
I'm following the development of Timesplitters Rewind and it's shaping up nicely. Hopefully they will finally release it this year, but I'm not holding my breath. Same classic action but on PC and with good graphics.
Return to Castle Wolfenstein, man... I actually felt some kind of remorse killing those elite guards back then... Not anymore, hah! I need to play that again with mods. The screenshots look good.
Soldier of Fortune 2. I spent way too much time massacring unarmed civilians in that one. I remember specifically me and a friend killing that one maid in the mansion level over and over... I've tried Fortunebabes etc. already and can recommend. Makes this otherwise mediocre game (yeah, the singleplayer is kinda eh) fun again. Only downside, is that there's just one female voice.
I don't know why the old arena shooters haven't been mentioned, yet. Quake 3 and Unreal Tournament had a decent variety of female characters to choose from, as well. Maybe they don't qualify as Zakos, because you don't fight large amounts of enemies at once and they can actually put up a good fight. I guess you can always turn the difficulty way down or use cheats.
Nice feature in Quake 3: You can actually chat up the babes, when you're not too busy killing them. That game had a really impressive chat AI for the time, that went way beyond just taunting and trash-talking you. The female bots actually respond to flirting attempts. Check out a conversation here: