RTS
Command and Conquer the original, then the original red alert, also C&C Retialiation for PS1 awsome fun playing linked till the they overheated after 4 hours.
FPS
BF1942 modded to DC.
Shadow Warrior this game was awsome.
Original UT <- How could people not mention this?
?
Original Quake, 16 player multigames at highschool, oh the fun.
Racing
Toca Touring cars 1 & 2
Need for Speed < the original old ones that actually involve police.
Morrowinds not bad, just to plain for me.
Also Et's ok but slightly boring after a while.
The reason we dont see games like this now, is the cost of producing games, its in the millions and so the companys arent prepared to take such a huge risk, which is why we are seeing a lot of sequels at the moment.
But we are seeing some changes, eg EA's new NFS Most Wanted has finally got police back in it and looks like its going to be an awsome game.