Quite some people are cool enough to provide their amazing work for free - even for commercial use, so you do not have to break your fingers or brain to create that stuff.
That rocks. Thanks guys!
The nice country flags for linking to versions of that insult generator in other languages come from Mark James. You also find great other (not only) icon sets there:
Prekesh Chavda created the tiny but clean social website icons. The icon pack was bundled and published by Orman Clark / PremiumPixels.com
That tasty ham that is insulting you is a work of photographer Renee Comet, and is public domain:
http://www.cometphoto.com/, Image at National Cancer Institute
The portrait of William Shakespeare is put in public domain by Perry-Castañeda Library / courtesy of the University of Texas Libraries, The University of Texas at Austin:
A selection of portraits of historical figures from the Perry-Castañeda Library, University of Texas at Austin.
The 100%-CSS-Buttons were created online at CSSButtonGenerator.com