Happened to me
While I was working at a university in the computing department, we had a student from the engineering school (which did an MSc in Information systems) come across asking to use the SPARCstations and the Oracle DB for her summer project. I set her up with logins and gave her some minimal help when she'd needed it.
Near the end of the project, I was in the lab reinstalling the servers (we gave them a clean build over summer) she thanked me for the help (which had been minimal) and asked what I liked to drink. I said whisky, half expecting a half bottle of Grants or something to appear and was rather shocked when she came back a few days later with a 70cl bottle of Balvenie :)
Given how little help I'd actually provided, I was rather shocked, but wasn't going to say no :)