SpeakTime is a speaking clock application for OS X 10.3.9 and up. It allows you to schedule spoken reminders in the voice and volume of your choice, show multiple desktop clocks with different time-zones, and speak the time in a more sophisticated manner than the system clock. There is also an optional animated dock icon.
This application works fine without registration but if you register you’ll be able to access some extra styles of clocks. It’s easy to add your own custom clock images by creating a folder of three tiff files, one for the face, and one for each hand.
It’s also easy to add new reminders by command-clicking on a desktop clock, or change existing ones by alt-clicking. Clocks can be on the level of the desktop, ignoring clicks, floating, or treated as normal windows, and can be up to 256 pixels wide.