Oh there are lots of things... The 100 pushup challenge as you said; using a crock-pot - you can't buy them in Denmark, so I'd never have gotten hold of one if it wasn't for a dear LJ friend who sent me one; switching from pads to the mooncup (which I LOVE), reading heaps and heaps of books that have been recommended to me by people here...

I'm probably forgetting something really obvious, but that's what immediately sprang to mind.