Many games, but I will list the ''hardest'' ones here:
Catherine (quite easy once you get the hang of the game rules)
Vanquish (Challenges were a pain, never again ty very much)
Wipeout HD (a very enjoyable plat, certainly with background music)
Killzone 2 (Beating Radec on Elite the fair way was a pain, then I did it a second time (full plat + all dlc trophies), but then I just shot Rico down before entering the room, activated the cutscene, and immediately ran back, it was way easier that way.
I never say no to a challenge as long as it takes skill, I absolutely hate luck based trophies.
And I am willing to waste my time as long as the game is good.