Magic Script Creator lets you build custom, fully functional AppleScripts by answering a few simple questions. You can then view the code of the script you just created, and make more advanced edits to further your understanding of the AppleScript language.
Create photo slideshows complete with transition effects and music.
Plug-ins appear in Coda's menu, and can be bound to specific keyboard shortcuts.
Create installer packages.
Free AppleScript based tool
Tasty time management game for Mac.