Minimal Xcode installation without iOS SDK
Solution 1:
In early 2012, Apple started packaging "Command Line Tools for Xcode". It's a much more manageable 140 MB.
Solution 2:
When you run the Install Xcode and iOS SDK installer, during the "Installation Type" step, you can uncheck the iOS SDK box, and leave the Xcode Toolset checked. This will skip the 8.35 GB iOS SDK install.