This bike concept could quite possibly be the weirdest we've ever come across. Aside from being impossible to ride, you need to keep your weight evenly distributed for maintaining balance. Thankfully, the See Saw Bike is just a prototype...for now. Click here for first picture in gallery.
Thankfully, the See Saw bike is only in the prototype phase because if you didn't flat out crash and burn trying to ride it (with someone of equal weight), you would surely go brain dead repeatedly head-butting your partner.[via Gizmodo - Myatomicmass]