This is code golf. I mention that because apparently some people are missing the point, which is purely to get the smallest size. This isn't directly applicable to most work you might do, but like many exercises that explore the extremes, useful knowledge can be learned from the attempt.

In a similar vein, there's a classic article on creating a tiny ELF executable.[1]

1: http://www.muppetlabs.com/~breadbox/software/tiny/teensy.htm...