Mine would be similar to BettaBaby, and a few others. I'd pay off the house for my parents, buy myself a new car, and a new house, give my brother some money (lawyers are after him cause he owes so much money), and set up a Wildlife Sactuary/Zoo, where I could rescue injured, abused, neglected animals. And within that sanctuary, I would love to have a fish room/aquarium, and I would buy all the top of the line products for all my animals.
In addition to that...I have always had a passion for the wilderness. I would buy A LOT of land and preserve it.
The place I work at now, which is a Science Museum, has a Wildlife Sactuary with about 50 species of injured, abused, and neglected animals, a lot of which were at once pets but were dropped off. I only volunteer in that department, my real job is in maintenance/facilities...like building and fixing exhibits, and just keeping the inside and outside of the building in good condition.