Yet another way to buy
While it's the same thing that Square Enix starting selling on its digital store last year, Final Fantasy VII has come to Steam. Priced at $11.99, this revised version of the classic has cloud saving, achievements, a character booster (don't give in!), and a number of other miscellaneous changes as detailed here.
It's worth pointing out that, like the digital PC edition of FFVII available directly from Square Enix, you will similarly need an account with the company for your cloud saves. So if having to register with Square Enix is enough to put you off from purchasing this, be warned.