soggy doggy 🏳️🌈
lcamtuf 
I don't know where you folks get your non-orientable manifolds, but the experience of ordering from Cliff Stoll at kleinbottle.com is second to none
Miod Vallat@lcamtuf I've been considering ordering one for ages! Still not decided, but these pictures are quite a strong incentive.
Insecurity Princess 🌈💖🔥@lcamtuf I can't believe he's still doing that so many decades later
Mirrors And Stuff@lcamtuf I still find his book great fun. I hope he's happy.
Brian Clark@mirrorsandstuff @lcamtuf I saw him speak at a conference in May and he was great. Full of energy and he seemed really happy! He stuck around after his talk and spent time talking with everyone.
Irenes (many)@mirrorsandstuff @lcamtuf he seems happy :)
Justin Azoff@lcamtuf I was going to buy one of the glasses, but I wanted to use it as a actual drinking vessel.. he had a faq mentioning how that's a bad idea because you can't easily clean it :-(
Chris Petrilli@JustinAzoff @lcamtuf I have one of his hats, and adore it.
Willem Janssen@JustinAzoff @lcamtuf That makes no sense. For regular glasses you have to clean the inside *and* outside, but for this one you just have to do the … uhhh … one side.
@JustinAzoff @lcamtuf yeah we have one, we have used it a few times, but indeed it's not the easiest thing to clean
Tadeusz Sikora
Glyph
SnoopJ
mkj
Simon ZerafaThat would look good next to my Utah Teapot 🤔🙂👍
Bob Young
Ko Simon toku ingoa 
@lcamtuf I wonder if one could be made (I know it technically wouldn’t be a Klein bottle, but designed to look like one) which could fit in the space of a pump bottle (to fit in my bag’s drink bottle holder), and be easily drunk from.
Stephen Wuebker@lcamtuf Y2K compliant!!
sky-guided@lcamtuf holy bap he's still at it
Mike Dank
Infinity
Ross Smith@lcamtuf Can confirm! The "Klein Stein" is a real treat for a Father's Day gift, too.
@lcamtuf Father and son bottles for me and my lil math nerd. (Also yes the paperwork and stickers are hilarious)
Advanced Persistent Teapot@lcamtuf omg how did you know I needed a birthday present for my pure maths degree holding brother?
awk
Sylvhem
Stephen M. Cameron@lcamtuf I like that he keeps his stock of klein bottles underneath his house, and uses an RC robot to fetch them. https://www.youtube.com/watch?v=Mw54zsON4MI
Fetching a Klein bottle from under Cliff Stoll's house
@CapnSpaceNerd @lcamtuf cool video, thanks for sharing. And for sending me down a rabbit hole 😉
@lcamtuf oh for sure. we get ours from him as well :D
Benjamin Schröter
Alastair McBain 
@lcamtuf Oh gosh, he is so wonderful. I used to give out Klein bottles to people who left for other jobs or to go back to teaching at uni at a place I used to work at maaaany years ago.
At first he thought due to the number of orders I was replacing broken ones so I had to assure him they were all fine as far as I knew. 😄
--
Edit: I wasn't exactly rolling in dough then--not that I am now either I suppose--so they went to people I knew well enough or were in my group not the entire company.
Paul Mietz Egli@lcamtuf OMG this is the same Cliff Stoll who in the 1980s tracked down a hacker who was trying to get access to US military computers! His book about the experience (“The Cuckoo’s Egg”) is a great read even today.
Pol Dellaiera@lcamtuf I got mine years ago, I love them :)
Bas Haenraets@lcamtuf I’ve never quite understood the klein bottle. It supposedly has only one side, but looking at the photo I’d say you should be able to fill it with water. The moebius strip I get, but this one… Nice object to own, nonetheless!
@bashae Mobius strip is a two-dimensional surface, but you can only "realize" it in three dimensions by twisting the strip. If you tried to make it in 2D, it would have a portion that self-intersects.
Klein bottle is a three-dimensional surface, but you can only "realize" it in four dimensions by temporarily taking the neck out of our three dimensions so that it can pass the body unimpeded. So yeah, any 3D implementation we can build is self-intersecting and thus not real.