Haskell
Haskell-platform includes ghc and cabal. When I install it into my Snow Leopard, I got an error "There's no software to install". The reason was the downloaded pkg file was corrupsed (smaller than real file). So I downloaded it again and successfully installed.
2.3 Mac OS X 10.6 (Snow Leopard)
Haskell Wki Mac OS X 10.6
Install the Haskell Platform
To uninstall ghc call: sudo /Library/Frameworks/GHC.framework/Tools/Uninstaller