I’m getting tired of having trouble deciding where to put albums and individual songs when I rip them. Compilation albums are particularly troublesome. Strict hierarchical file systems don’t make information accessible in common sense ways. So I’m wondering – are there any tools that allow one to organize music using tags, much like one organizes bookmarks in Del.Icio.Us? For instance, it’d be great if I could find and gather all the songs I own that have a Celtic feel or all the progressive rock without copying or moving any files. Anyone out there know of such a tool?