the most innovative young enterprise group I've heard of designed a 2 minute survey that estimated your carbon dioxide emissions, and calculated a number of trees to offset a certain fraction of it...
they then got a company to plant the trees.
it was pretty epic thinking, but they did get a lot of help from the school.
I wasn't really fussed with making a profit (shock horror) but I did want to make a professional quality product that I could feel good about... something that I could see in the shops. my good friend is a pro in photoshop, got him to design some modern/alternative designs (my favourite was the 8-bit heart design) and had the badges mass produced.
was expensive and didn't make much of a profit, but they were good quality badges, we sold lots to our mates at a good price, and I'm proud of them =]