We've rewritten MoonMenu from the ground-up in Cocoa. It sports a beautiful fading window with collapsible panels, gorgeous moon images, and a really cool control that you can use to scrub the current lunation (New Moon to New Moon.) MoonMenu is just an app. Nice and clean. And filled with Cocoa goodness.
We haven't updated MoonMenu since 2001. (Has it been 6 years?) It was one of our first Carbon apps. CarbonLib, even. It's nice to have it back!