Mootools 1.4.4, HTML, CSS, JavaScript
javascript flow control: async each
Mootools 1.4.3 (compat), HTML, CSS, JavaScript
No-Library (pure JS), HTML, CSS, JavaScript
Mootools 1.4.1, HTML, CSS, JavaScript
jQuery 1.7.1, HTML, CSS, JavaScript
jQuery 1.7, HTML, CSS, JavaScript
http://avva.livejournal.com/2379371.html Get 21 from 1, 5, 6, 7 using each number only once and 4 basic arithmetic operations http://en.wikipedia.org/wiki/Reverse_Polish_notation
Crazy stuff involving function to string decomposition.