KeyUp is a free and user-friendly on-screen keyboard application with several built-in themes and sound options. You can experience a clacky, mechanical keyboard or a classic typewriter sound. Limitations: Currently, this program only supports the US keyboard layout.
Wineskin Winery creates Mac OS X ports/wrappers for Windows programs/games, with an easy-to-use GUI, integrated Wine, X11 and an installer.
LiquidMac uses a particle system to imitate liquid and responds to laptop orientation.
