Like it or not, these bikes are coming eventually. Personally, I think it's cool as hell. Think of the urban areas where a loud, non-street legal dirt bike would be a total bust. Like BMX street sessions, without all that pesky pedaling around part. I don't know who can afford 7k for one, but as with all technologies it's bound to come down if they can get some sales volume. This one sounds pretty neat, and as a bonus if you get stranded you can eat the battery!
link: Zero X