Something that bugs me about ST2 is how differently it treats Folders and Open Files. I think it would make more sense to change "Folders" to "Current Project" and allow files to be added. Currently, when you drag a file to the sidebar, it opens in the "Open Files" but is not added to the project. When you right click on a file in the Open Folder's section, you get a context menu (mostly populated from the Enhance Sidebar plugin). Right-clicking on an open file only gives one option: close file. This causes some limitations for projects that only have a few files that are not in the same folder.