It work's for all games which asks for this. At the moment I have only heard of one, but other should be the same:
COD2:
Use regedit and go to HKLM\SOFTWARE\Activision\Call of Duty 2 and add a string value to it entitled codkey. Now edit it by inserting a key from a keygen, or something (without the dashes).
COD2:
Use regedit and go to HKLM\SOFTWARE\Activision\Call of Duty 2 and add a string value to it entitled codkey. Now edit it by inserting a key from a keygen, or something (without the dashes).