In that vertical GC shooter whos name eludes me right now (the one with the black and white energies) you unlock the special modes by EITHER finishing the game with some restrictions
finish game : special bit 1
finish game without getting killed : special bit 2
OR playing the game for a set number of hours
there is no way I could ever complete that game but I could still get access with enough commitment. Play the game a few times as far as I can go and then I get rewarded for trying.