My boss bought the grad students an air popcorn popper for the conference room. However, being graduate students, one of them brought in some popcorn, everyone ate it, and then no one replaced it. They are actually quite generous about bringing in food for birthdays, etc, but popcorn is not one of those things you think about at the grocery store.
As a joke, I told them I would buy them a big bag of popcorn at Sam's Club. However, it turns out that the bag is 50 lbs. I didn't think they could go through that much popcorn, but then they went through a 2 lb container in about a week. So when I was at Sam's Club this weekend I bought them the 50 lb bag. It was $18. I'm starting a pool about how long it take for it to get all eaten.
1 big bag = 630 servings
19 students and postdocs
I am guessing March 31.