- Go to Klondike, go back 500 years in time and dig up all the gold. Go back to our time and build a skyscraper entirely out of the gold. Rent out the apartments.
- Go to the Weimar Republic in 1923 and get a sack of high value banknotes. Back up a few years and buy tons of land. Go back to our time and throw the biggest party mankind has seen and sell beer and hot dogs there.
- Go back to when Queen Elizabeth was young. Seduce her and take pinup photos of her. Go back to our time and sell them on eBay.
Continue the list!