It happened as I was about to loose my mind in one of the last sequences of that marvel called: Psychonauts.
I just could not reach a place after much jumping and the sequence kept repeating itself.
As I was falling down once more to my brief demise, and was about to make a pact with some dark God to allow me to reach that ledger, the screen had a momentary "Matrixy" effect and when I revived I was up there. On the ledge. Where I wanted.
After carefully examining my room for any evidence of my blood spilled on any sort of ancient document, I continued the game and just a few minutes later I was triumphantly looking at the final credits.
I am rather happy that the glitch occurred at that moment, or I'd be a docile intern in some sanatorium, or the unhappy toy-boy of a hellish deity.