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sure it's possible....just be sure you put it on the same side of the dock's divider bar as the trash can because it wont go on the dock if you try to put it with the applications
 
Just becareful not to drag your folder(s) too far to the right, or you might end up trashing your files.
 
If you want your folder on the Applications side of the doc simply add ".app" to the end of the folder name.

The you drag it into the dock. The you rename it to remove the .app and the generic app icon.
 
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