There aren't any known 'Hacks' for Prestige on World at War. there is however, a prestige glitch. basically when you reach level 65, you prestige, and then 2 seconds later, unplug your Ethernet cord from the back of your PS3, then turn off your PS3. and when you turn it back on you will be the next prestige but still level 65 and you just keep repeating that until your at the desired prestige level.