Metronome is, umm, a metronome for Mac OS X. (Requires Mac OS X 10.3 or later.) It's not perfect, but I think it's pretty good.
Analog Clock is... an analog clock. Resizable with your mouse, can display day and date, change all the colours around to suit yourself. Comes without a menu bar. Access menu items with a right- or Control-click.
Change Case is a service with which you can change the case of selected text from the Services menu. There are five options: ALL CAPS, all lower, Word Capitals, tOGGLE cASE and camelCase.
Insert Current Date is a service with which you can insert the current date into any place you can type, such as a text document or text field.
CocoaAccessorWriter. If that name means anything to you, you may be interested in this. It's a free, but pale, imitation of the real thing, namely:Accessorizer, by Kevin Callahan.
Speed Match II is a tile matching memory game with a timer. My first programming effort. It ain't great, but it does work. (Requires Mac OS X 10.4 or later.)