SSAO is a really popular technique these days. Before SSAO there were parallax mapping and lens flares. One thing that bugs me when it comes to the majority of SSAO screenshots is that most of them seems to have wrong gamma curve.
A typical SSAO buffer contains linear values from 0 to 1. Since the buffer is linear it will tend to look harsh or too dark when displayed on a regular PC monitor. The standard gamma for PC is around 2.2, so the next time you're posting screenshots of your SSAO algorithm, please correct the image with pow(Pixel, 1/2.2) first. :)
I might as well post an image of my SSAO implementation (quite old now). 16 samples distributed randomly in a hemisphere. With a non-fancy box filter. And gamma corrected.