Generally, whenever one of his absurdly complex plans actually works, such as the way he managed to drive his car from an armchair on top of it due to it being full of January sales shopping. Unfortunately, that one plan didn't stay successful. Luckily, his car ended up driving into a truck full of pillows.
His appearance at the 2012 London Olympics playing a tedious piano note over and over in the "Chariots of Fire" sequence.
Meeting the Queen (in the animated series, not the live-action one; we all know what happened in the latter…).