My impression is that "hi, can I buy you a drink?" is cliché but I don't know what reasonable substitutes are.
"Hi, what's your name?" or "Hi, I'm Qiaochu" (depending on the cultural context, e.g. ISTM the former is more common in English and the latter is more common in Italian). Ain't that what nearly any language course whatsoever teaches you to say on Lesson 1? ;-)¹
Or, if you're in a venue where that's appropriate, "wanna dance?" (not necessarily verbally).
(My favourite is to do something awesome in their general direction and wait for them to introduce themselves/each other to me, but it's not as reliable.)
I conjecture that "Hi, I'm Qiaochu" is a very uncommon greeting in Italian :-).
r/Fitness does a weekly "Moronic Monday", a judgment-free thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. I thought this seemed like a useful thing to have here - after all, the concepts discussed on LessWrong are probably at least a little harder to grasp than those of weightlifting. Plus, I have a few stupid questions of my own, so it doesn't seem unreasonable that other people might as well.