See that bottle, it has no volume! Well, mathmaticelly it has no volume, but phisically it is capable of holding liquids. It’s hard to see from that picture, so here is a cutaway of one that should show it better:
Follow the line made by the glass. It is one continuous line, you never cross. It is a mobius strip, in 3 dimensions. Actually, a true Klein Bottle exists only in 4 dimensions. But since we humans can only manupliate matter in 3 spatial dimensions, we must emmerse it in 3 dimensions. I could explain it to you,but all I would be doing is copy & pasting from here, so I’ll just give you a link instead.
There’s a ton of information on the site, and my favorite part of it all is the subtle humor injected everywhere. One of the best parts:
we’ve painted them in your choice of any color as long as its Black. In Canada, Britain, and other commonwealth countries, they’re available in the colour Black
Notice the spelling difference in color. That kind of British humor is all over the site, and I love it.
If you want something else as a conversation started, try the Tantalus Cup:
That cup has a siphon in it, ans oncet the liquid reaches a certain level, it starts to siphon it out the bottom. A great albit messy cup to have around.
You can buy all these and more right over at the Klein Bottle HQ which conviently is just a click to the left away!