Add recent items to Dock

defaults write com.apple.dock persistent-others -array-add '{ "tile-data" = { "list-type" = 1; }; "tile-type" = "recents-tile"; }'

I can't remember where I got this from, but the link in the title takes you to a page with more of the same....

As do:

• http://secrets.blacktree.com/
• http://www.macosxtips.co.uk/index_files/terminal-commands-for-hidden-settings-in-leopard.html
• http://www.macworld.com/article/132447/2008/03/leopardsurvival2.html
• http://www.ss64.com/osx/defaults.html