Know what you're doing on a fixed gear bike or be ready to "crash & burn". A fixed gear bike is THE most simple type of bicycle (next to a kid's bike) because of the lack of extra parts. It has only one gear or speed...and it's FIXED. In other words - you pedal ALL the time - forward or backward. There is no coasting on a "fixie". If the bike is in motion - the pedals are in motion.
Fixed gear bicycles (or Track Bikes by the proper name) started on Velodrome tracks. True track bikes have no brakes because there is no need for brakes on a Velodrome track. The rider has the opportunity to slow down gradually after a race & not lock his knees to stop as on the streets in an emergency situation.
To me - they are nothing but a fad or craze started by the recent economic downturn because most people today can NOT afford a good road bike with gears...about $650 and above. Fixed gear bikes can be found much cheaper because they have no gears, derailleurs & sometimes - no brakes. Law dictates that all bikes used on the streets have brakes on at least one wheel. Doesn't mean it will always happen.
Buy one if you want to... But as stated - be ready to fall a few times under emergency stopping situations. They do go fast...on flat land only under the right circumstances. Riding uphill or into a stiff breeze - forget it! 90% of the time (or more) you'll be in the wrong gear because there is only ONE gear. It's hard on the knees & other joints in the body.
Now if you want a good road bike that could blow your friends (???) away - see link below. This is a damn good road bike that can climb hills faster, stop faster & most of all - you can change gears as needed for whatever the existing conditions are.