A Reddit user participating in the annual redditgifts Secret Santa gift exchange got a major surprise this week when she opened her card and package and belatedly came to the realization that “Bill,” her Secret Santa, was none other than Bill Gates.

And yes, he included a picture (above) to prove it.

The Reddit user, named Rachel, is understandably very excited about all of this, judging from her post about the experience, published this afternoon.

“My god,” she writes. “Never in my entire life did I imagine, ever, ever, ever that Bill would get me (as a match). I am SO SO thankful for the time, thought and energy he put into my gift, and especially thankful for him overnighting it.”

OK, so what did Gates give her? A cow, of course!

To be specific, he purchased a cow in her name for a family in need via the non-profit Heifer International. A spokesman for Gates explained to GeekWire that this was one of Gates’ motivations for participating in the program, to help bring attention to this cause. Gates also had a great experience doing an Ask Me Anything Q&A with Reddit users earlier this year and wanted to continue to participate in the community.

As it turned out, the donation dovetailed with Rachel’s own passion for education, because Heifer also provides money to help girls around the world go to school.

Gates also gave Rachel a travel book, Journeys of a Lifetime, based on her interest in travel — another spot-on perfect gift, judging from her reaction.

Check out Rachel’s recap here, with more pictures and a hilarious p.s. to Gates: “Sorry for the apple ipad on my wishlist, that was really awkward.”