While the folding bike concept is cool, and it's actually really handy to be able to take them on trains where a non-folding would be disallowed, and while they are also more convenient than a full size bike, they're still big and cumbersome when folded up.

I can take mine on the bus, but that wouldn't be my first choice. I can take a regular Lyft, but not a Lyft Line with it. (I mean I could, but that's a dick move.) You're "that guy" at the bar after work.

Like I said, I own one (well, a Dahon), and it's definitely useful, more convenient than a full size, non-folding bike, but it doesn't actually solve the issue, merely alleviates it somewhat.

Agree, you need something like the below to make it work, but it'd be a revolution in transport! http://www.bike-intermodal.eu/

Note that the A-bike falls into this territory, bar the tiny wheels http://www.abikecentral.com/index.html

Edit: I'd forgotten about another type, the monowheel, though they do require some skill: https://www.airwheel.net/home/product/X5

...and for normal bikes this would be a quick and easy win in many cities:

https://www.permaculture.co.uk/readers-solutions/public-tran...

Or a Bike Friday Pakit https://www.bikefriday.com/folding-bikes/product/bike-friday...

The Brompton is really the only game in town for urban folding bikes. Uniquely, the Brompton locks into a compact and balanced package that can be comfortably carried in one hand. If you opt for a model with a pannier rack (or buy an EazyWheels kit) the folded bike can be pulled around like a wheeled suitcase. There are lots of good folding bikes, but only one good folded bike.

https://www.youtube.com/watch?v=cepoV17TH-A

Depends on what you're looking for. I found the wheel size a bit too small.

I think this is a fair comparison and gives the advantage to the Brompton in small folded size, although its weight is not something to be taken lightly (!) http://anatolyivanov.com/prose/en/AI.7.00109/

I love the Pakit, however I like the looks of this: https://www.youtube.com/watch?v=4mkzRF3trJM https://youtu.be/xscDjAmD2MM?t=251