TITLE: What's a great christmas present for someone with a PhD in Mathematics?
QUESTION [92 upvotes]: Christmas is just around the corner and I haven't bought all the gifts for my family yet ( yeah, )
My Dad has a PhD in Mathematics, he works in Graph theory and his thesis was about Quasiperiodic tilings.
What do you think would make a good gift for him?
I'll appreciate anything you could think of!
Thanks for reading, hope you have a great day .
p.s.: after reading all the tags in this website I think this is the right one for this kind of question? please correct me if I'm wrong!

REPLY [3 votes]: A book of interviews of famous mathematicians could be good. I have in mind particularly More Mathematical People, which I've gotten a lot of mileage from here at MathOverflow.

REPLY [3 votes]: A good red wine from Bodegas Langa (Spain)