HTML Purifier : HTML Purifier is a standards-compliant HTML filter library written in PHP. HTML Purifier will not only remove all malicious code (better known as XSS)...
PHP unified diff patcher : A powerful class which allows to create and merge unified diff patches into any file. Fully written in PHP, uses the GNU standard unified diff format ...
Parsley.js : Javascript forms validation.
Powerful, UX aware & Dead simple.
pChart : pChart is a PHP class oriented framework designed to create aliased charts.