just like the title says

if you find a code that doesn't work let me know

first code:
FF7- Take Jessie's Pay

there was a code that said you could wait a while in the very begining (after planting the first bomb) and leave jessie behind and get her pay, not true all that happens is that you blow up with the materia factory - Game Over

i havent been able to get the cheats to work for quake3. ive been experimenting with the the 3rd person view, but the commands to change the angle and range of the camera are only available if cheats are enabled. i know how to get the cheats to work (sv_cheats 1,etc,etc) but in-game it still doesnt allow cheats. it works with other games, so why cant i get it to work?

FF7 had a multitude of cheats, codes and secrets that were flase the most famous of which is the Aeries thing (obviously fake, I know as i did everything possible and got evey item possible to get)

The wooden chocobo also fake (again same reasoning as the first)

Sephiroth on your team can be done with the game shark but leads to many problem, seph always has to be in your party and the game plays like it does in the flashback (ie Seph gains no levels or materia and you cannot change his skills/equipment making him great until the mid point of the game then he is simply a nuisence.

Multiple endings in 7 also fake they never show a seen for Yufi or vincent (whether you have them or not) so there is no seperate ending for them

Umm yeah I am sure there are thousands of others but yeah

As fr the quake thing I do not know, I saw cheats done on Quake one a long time ago and even then they were awkward the only thing I can think of is make sure that your game matches the game you are getting cheats for (ie version 2.7 or whatever they have) many times cheats are taken out/added and/or changed.