Some random DS game I used to have.
It was called nanotray. Man, that thing was hard as hell!
I died so many times on the first level. I just got angry and returned it the next day.
I think that is it.
When I was young, it was Sonic the Hedgehog 2. Now? *censored.3.0*ing Prinny: Can I Really Be the Hero? is the hardest game I've ever played and actually beaten.
meat boy is really recent, haven't yet finished it, and it's only difficulty really lies in the level design.. not anywhere else. you basically ram your head against the wall for 5 minutes until you learn the timing. no lives, continues, powerups.. just pure platforming bliss.
probably something with godawful controls, though.