Upbeat Happy-Time Music

I'm finding lately that I am more and more impressed with musicians who can produce upbeat music. I think it has something to do with that Bart Simpson quote: "Depressing teenagers is like shooting fish in a barrel" - the sort of angsty-young-person vibe is too easy. Happy music takes some effort.

For example, this:


Or this (and yeah, I know, it the song of theirs you always hear). And to me, I can even hear some pain behind here, but transformed into a cry of joy at the world: