Lots of links:
Become a gmail master
gmail keyboard shortcuts
zventstools - Interesting Rails plugins
ajaxload - Make funky ajax loading buttons
cheat sheet for microformats with rails
interesting bookmarklets
using tinymce in rails
cached_model - cache models in rails, from our friends at the robot co-op
time based fragment caching with rails
MySQL UPDATE - How to update tables in MySQL
animator.js - This so rocks, it's a simple way to do funky javascript effects in a prototype.js compatible way, much simpler than scriptaculous, you can transition between two CSS views of an element. sweet.
backgroundrb - A way to run processes in the background from Rails.
funky audio electronics projects - spookyarduino
centering with CSS
CSS Centering - fun for all!