Retirement Social Security Benefits Calculator

http://www.ssa.gov/OACT/quickcalc/index.html

Lessons Learned - Lean Startup

http://www.startuplessonslearned.com/2008/09/great-open-source-scalability-tools.html

Good website of Brain / Memory Games

http://www.lumosity.com/brain-games/memory-games

Puzzles to sharpen your programming skills

http://www.coderholic.com/10-more-puzzle-websites-to-sharpen-your-programming-skills/

Let's Build a Compiler

http://compilers.iecc.com/crenshaw/

Twitter Alias

http://blerg.dominionofawesome.com/doc/

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