Mono

Mono is an effort to create an open source implementation of the .NET development framework.

• The MonoDevelop IDE (there’s also SharpDevelop)
• Some apps: Dashboard, Blam (an RSS aggregator), Muine (a music player).
• Mono on the Mac, official page
• Bundles for Standalone App Deployment

• IronPHP - the beginnings of a PHP port to the CIL
• IronPython - an interesting (if still somewhat limited and less than open) port of Python.
• Boo, a Python-inspired language

• Why Mono Is Currently an Unacceptable Risk
• Miguel’s Response
• Andrew’s Take