http://dean.edwards.name/packer/
Dean Edwards javascript packer. Copy / paste some js code, it'll pack on the fly for you. Including the option to shorten variable names, and even base64 encode for super duper pack'ed ness.
http://wordpress.org/extend/plugins/wp-js/
The WP JS plugin combines multiple javascript files used by WordPress into one single, gzipped file for faster download, fewer connections.
http://lindsay.id.au/code/2006/faster-javascript-sorting/
A great article on how to implement multi-dimensional array and object sorting in Javascript in the most efficient manner. The article compares the speed of multiple approaches and provides code to implement the fastest approach.
http://www.i-marco.nl/weblog/archive/2007/05/27/on_a_quest_for_ultimate_websit
May 2007 - A guide to optimising WordPress focusing on browser led optimisations such as fewer http requests, spreading images over hostnames, and so on.