I have one fixed gear bike, and of all my bikes (tall bikes and swing bikes included) the fixie scares me the most. I had the privilege of riding a critical mass with a bunch of guys on fixies (I was on my tall bike) and I gave them much props. I can't figure out ANYTHING on a fixed gear, not even a bunny hop... how do you plant your feet while the pedals are always moving? I can even bunny hop my tall bike!!!
You do feel more a part of the bike though since you are always connected to the spinning wheels, you have to think fast and plan ahead a lot, you know... or die. Maybe one day I'll get the hang of it.