Folding bikes have tickled the imagination and creativity of bike designers. Here are some unusual ones that I found today. Please add more as you find them.
This one reminds me of the tilting motorcycle trike called the Carver One, but with the single wheel in the rear and dual wheels in front: https://www.youtube.com/watch?v=sLmhYS6Fm9o.
This one brings a new dimension to the idea of packing your bike in a suitcase for travel on public transport: https://www.youtube.com/watch?v=hZiQ1jPw4I0.
Now, this one doesn't fold, but it has all folders beat when it comes to portability:
https://www.youtube.com/watch?v=bPBwuP73SK8 . Brompton owners, eat your heart out.