$5 Amazon Gift Card code with access to an .edu email address. Just took a quick 45 second survey and got the code in a few minutes.

Found it on craigslist by chance, was a bit skeptical. Basically, they want to know if where you went for your spring break trips and what they were like. It took me about 45 seconds to answer the questions. They'll send you an email through your .edu address and you just have to reply to it in any way. They sent me the code back in a matter of minutes. LINK

EDIT: Although I did not receive this, one user reported a three sentence minimum response on some questions. So you're looking at a bit longer than 45 seconds to respond to the survey.