Failed inventions compilation - GIF

[bruce.desertrat]

The first one is more 'art bike' than invention; I seem to remember seeing it somewhere before. The second is very much like the modern elliptigo https://www.elliptigo.com/, the tiny bikes are still sold today https://www.unicycle.com/udc-mini-bike/ (plus dozens of DIY builds scattered among the internets. )

Here's a lot of bike sail designs