Seatpost Security

correct. California law requires a working brake on a bike. here in Davis California, 90% of fixed gear riders ride brakeless (hillless terrain) but are downed by the anal bike cops that pull them over for not "following" the law. so we are trying to work around the issue~ we're not cheating the law; the law is simply outdated and incorrectly written to not take into consideration that our drivetrain is a viable part of a braking system. just doing that we dont get bothered by the police.

right.

but I dont understand your brake setup. besides the legal skirting, what's the point? you already have a brake lever and caliper mounted - why not mount it in a position like a normal person thats a) easy to reach b) offers better braking c) doesnt look retarded. I think the answer is aesthetics and an attempt to kept your bike "minimal"...but, in my opinion, a brake mounted like yours simply looks stupid and a normal brake setup would look much better not to mention reasons a, b, and c listed above.

what you've done is akin to skirting a mandatory helmet law by attaching a helmet to your arm instead of your head.

so, in conclusion: total fail.

that bearing in hex hole sounds like such a great idea~ does something similar in principle exist for the wheel nuts? any ideas?
gluing bearings into your axles would be a horrible idea.
but yes, a solution exists: a d-lock/cable/locking skewers/quick release(s)