TinyMCE, an HTML WYSIWYG editor written in JavaScript, has moved to GitHub: http://github.com/tinymce

img http://img.skitch.com/20100115-m19rkf3wb3panm2fhnw5gb6h9u.png http://github.com/tinymce

Their announcement lists the main reasons they chose GitHub:

Community

Speed

Ease of access

Flexibility

Welcome to the party!