Yummy is a ruby del.icio.us API used to scratch an itch I had a few months ago.
Docs are here: http://smarticus.rubyforge.org/yummy/
Project page is here: http://rubyforge.org/projects/smarticus/
You can also install it as a gem: gem install yummy
Seeing as this is version 0.0.2, its kinda rough, but should improve now as I actually have a need for a ruby del.icio.us API for another project. Suggestions are welcome.