There's no sense of scale but this booster is as high as a 10 storey building. It balances by using a closed-loop thrust vectoring system. SpaceX are working towards a simple reusable launch vehicle that could (unlike the complex and costly shuttle) reduce spaceflight costs by a huge amount ...
Elon Musk also recently outlined a realistic plan for the colonisation of Mars http://www.space.com...-elon-musk.html