Chrome Developer Tool - Develop and Debug Chrome Apps & Extensions. By Google
SmallDevTools - Handy developer tools with a delightful interface
Profitable developer tools database - A database of 103+ hand-curated profitable developer tools
LaunchKit - Open Source - A popular suite of developer tools, now 100% open source.
YouTeam - YouTeam is a new, smarter way to outsource.
GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.