Electric bike that folds into a shoulder bag
engadget.com
engadget.com
The problem is, you still look pretty dorky/smug riding one, and it looks hella dangerous.
If you want something like this, just get an electric skateboard: http://www.exkate.com/
It is probably safer, and you might look sorta cool.
(see video)
For comparison, a Segway can do about 40k.