There is a typical
bisected flag design that's used in anarchist symbolism: the bottom-right triangle is always black, and in the case of Anarcho-Capitalism the top-left portion is usually gold or yellow. A decentralized movement can never have any official symbols, but that color combination does seem to be pretty popular. The flag design looks a bit incomplete though, but that's probably how it should be - it's just a template for individual people to customize, and there's a lot of room to add something.
I tried to come up with something simple that can be put in the top-left (yellow) corner to symbolize my views, which come close to Objectivism but not entirely. What I ended up with can be seen in my current avatar.
[The gears symbolize mankind's capacity to create useful things. The fact that they interlock but if you look closely don't really touch symbolizes individualism, and how individuals can deal with each-other on voluntary basis through capitalism, exchanging value for value. The horizontal positioning of the gears, in contrast to the bisecting slash below, creates a subtle illusion of a smirking face in gear-rimmed glasses, or a pair of hairy testicles (i.e. "balls of steel"), but that would be analyzing things too far. The left gear contains a little symbol of a bolt of lighting, symbolizing the feminine - inspiration, beauty that needs to be tamed, and fertility. The right gear contains a light-bulb (similar to the cover of Ayn Rand's "Anthem"), symbolizing the masculine - ideas, enlightenment, results, utility. They combine to turn raw power that exists in its potential form into things that make life better.]
So the theme of this thread is: what would YOU add to YOUR personal version of that flag, working within the established color scheme and template?
EDIT: for when I change my avatar later:
Subtle Watermark Version | | 
Top-Left Corner Detail |