Both Mac OS X Leopard and Snow Leopard come with a paltry set of solid colors for desktop backgrounds. This is easily remedied with ImageMagick (available for install through the MacPorts Project) and a quick hack. The script below generates all the background images for web-safe colors that should then be immediately available for use under the Solid Colors selection in the Desktop and Screen Saver System Preferences. You can copy and paste the script into Terminal, but you'll need to be a system administrator for it to succeed because it writes the images into "/Library/Desktop Pictures/Solid Colors".
I wanted to launch some scripts from cron (I know it's deprecated) that would mount some shares using AppleScript (so that share credentials are prompted via GUI or accessed from Keychain) and display notification through Growl. On first try, this worked under Mac OS X 10.5.5, but then began to fail after an upgrade to 10.5.6. I would find error messages that were not very clear: