Courseroot - Biggest online course database on the web
Codester - The marketplace for ready-to-use web development assets
Alcamy - Free, open self-learning platform. Learn & teach anything.
CodeCanyon - Scripts and Snippets From $1 for PHP, JavaScript, ASP.NET, CSS, Plugins, HTML5, Mobile and more
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PieceX - PieceX is a new platform available for buying and selling source code. All Engineers, From beginner programmers to senior engineers can use the PieceX. It provides source code in many languages including Java, C#, PHP ....