Nonetheless, I say go for it. You would learn a ton and probably become the best kind of coffee snob, one who can back it up with chops ;)

Careful about the drudge work though (especially cleaning floors/toilets at the end of the day), and if you're not used to spending all day on your feet you'll feel pretty sore at the end of the first few days!

I made the effort to befriend the baristas since I see them every day anyway. Eventually asked one of them to teach me during slow hours and I started to make my own drink each time I came in. One of them baristas ended up referring me to a different cafe (allowed me to avoid the awkward conversation of a weird looking resume) and I passed the interview by making decent drinks.

This line is beautiful. :)

Sometime's it's difficult for me to get motivated to push out code when it's just for myself.

They have such high margins on individual drinks (and people will totally buy a pastry if the coffee is free) that this shouldn't cost too much. Plus you can always make the puzzles harder, or have 2 or 3 easyish ones and then graduate people onto harder ones that they'll take a few days to solve.

You can imagine how to decorate the place - blackboards for walls, encourage the customers to use them to practise the spare puzzles lying around today, etc...

If I found a local cafe that paid that much attention to the experience, I'd certainly apply there. But I find many small cafes focus only on the coffee product, but not how the customer feels about the product.