What would you do with a time machine?

Followers of paralytic supergenius Steven Hawking (author of A Brief History of Time, pre-eminent physicist of our age, voice like an early 1980s arcade game) will know that the scientist recently published an article in Britain's Daily Mail entitled “How to build a time machine (opens in new tab).” [SPOILER: it's hard.] Obviously, the first question this raises is, “what would I do with one of those?” But with the obvious answer beingwell-worn territory (opens in new tab), what would you do? Meddle with gaming history, obviously.