I've been searching and looking for ways of achieving this; I want to have my own created "git" folder that I'm storing all my software projects in, and I want it to look like the old "Developer" folder that was created with earlier versions of Xcode.
The challenge I've been trying to figure out how to mange with is how to have it display the developer folder system icon, the folder with a hammer on it, without creating a copy of the icon and storing it in the folder, seeing as the current system icons is around 2 megabytes in size (bumped to 1024x1024 in Mountain Lion).
I've managed to find out that the icon itself is available in /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/
The regular ctrl+c, ctrl+i, ctrl+v or dragging the icon into the "Get info" dialog creates a copy of the icon, storing it as "?icon" inside of the folder itself.
If you compare it to one of your "regular" system folders they do not actually contain any icon file, but I'm assuming the .DS_Store in the parent folder keeps a reference to the actual icon or something...
Maybe you just think that I should suck it up and just create that copy, but its more the gist of things, I want to know if it is possible, and if so how. :)
So, any of you have a clue, please let me know!