Suggestions for a small gift for my research participants?

In my dissertation research I am interviewing a number of academics. They have to schedule two meetings for the interviews and I would like to send them a little something to thank them for their trouble.

Obviously I am going to send a nice note… but what else?

I was going to send them a recently-published article I wrote on a similar topic - most seem interested in my work - but it seems somewhat self-serving. I also considered giving away copies of my most recent book - but those are kind of expensive, even with the author’s discount! I’m considering a Starbucks coupon for a few bucks ($10?) but are there other ideas? Keep in mind that I don’t have much cash and I don’t know the subjects beyond the interviews…

Can you say very generally what field of study you are in?

A couple of movie tickets to the local art- or second-run theater would do nicely, I think. See if you can get vouchers that would let 2 people see the movie of their choice.

Kinder surprise eggs! It might amuse them, at least.

I’m in the social sciences, but the academics are from a number of disciplines.

Scrib! I think we have a winner here. We actually get a discount for tix at the school box office, and I think it shows a little thought, but not so much that they’d feel weird accepting it.

Good one. Mods can close this one, or if folks can take this in another direction, feel free. Thanks for the other suggestions as well.