Art: A wonderful showcase of 3D digital renders.
Customer Service: GetHuman promises to get you to a service representative faster.
Developers: The trajectory of a software engineer and where it all goes wrong.
PHP: Methods for increasing file upload limit.
Real Estate: Zillow is one of the best sites I have seen for finding houses.
SQL: SQL Fiddle (much like JS Fiddle) lets you "fiddle" around with SQL via the web.