Leaving it in the bank is an excellent option. You've got two main things to save for, a down payment for a house and your wedding. Better still is a balanced and sane investment portfolio, but leaving it in the bank is better than a bad portfolio, so take some time to learn how investing works if you choose to go that route.
Spend the money on a plane ticket to somewhere with women?
I emphasize social skills because, like Vitamin D, the hacker lifestyle leads us to be deficient in such a vital resource. We should be supplementing our lifestyle with lots of activities that force us to interact with other people in ways we're not used to. I've been going to the same bar for the last 8 years. It's often painful, I still don't really fit in, but it's been crucial for helping me develop my sense of self.
Another good place to frequent is coffee shops, but good neighborhood coffee shops are quite rare. Starbucks doesn't really do the trick, something about the atmosphere discourages the kinds of spontaneous casual community that you really need to develop social skills.
</sarcasm>
Luckily for the intrepid, giving the market something it hasn't seen yet isn't terribly difficult.
Develop some social skills. Best place to do this is a bar. As you get good it can double as your dating pool.
Hit the gym and go to shows.
I also bought a few expensive toys that I really wanted (nice high-end camera, for example) and take regular vacations to nice spots.
I started giving to charity, too. I also decided to do something closer to home and helped a relative with their student debt. I started taking some of the free time I have and that nice camera to do photography for a local charity.
Saving it (in an index fund rather than a bank) is an excellent thing to do with it. Keep living like a college student (or even a fair bit better than that), and save the rest, and you'll be able to retire in your mid-to-late 30s.
Resist the inclination to expand your expenses to match your income; it doesn't actually make you any happier, long-term. (Many different studies have confirmed this: increasing your level of spending tends to give you a short-term burst of happiness followed by a return to the baseline; it doesn't permanently raise your baseline.)
You don't necessarily have to retire early. If you prefer, keep working past that point as long as you're enjoying yourself. You'll be able to have a lot more flexibility in your work, and later in your career you'll be well into the territory of "start your own charitable foundation" or "don't bother raising a series A".
[0] https://personal.vanguard.com/us/funds/snapshot?FundIntExt=I...
Thought that might be interesting, it was to me (came upon it on HN).
cha-ching
That and invest.