Xamarin (Mono Droid & MonoTouch) are hosting a networking event on Monday 22nd July at the Grid (351 W Hubbard) from 8-11pm. Register at http://resources.xamarin.com/chicago_drinkup.html to help them estimate numbers
Next week((Mon 22nd July - Thu 25th July) there is a conference in Chicago on using C# for multi platform development, including Android, iPhone and Windows phone. The conference is called MonkeySpace: http://monkeyspace.org/
Miguel de Icaza ad other senior technologists from Xamarin will be presenting. Xamarin provide the MonoTouch and MonoDroid framworks allowing C# to be used to develop apps for Android and iPhone. The also provide the Xamarin Studio development environment, some licences of which even allow development directly in VisualStudio! Check it out!