TagFlow - TagFlow is an intelligent files manager that use tags for organize your documents.
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
Tabbles - Tabbles use tags to organize and find files along with your colleagues.
allTags - allTags is a free, tag based file management application.
TaggedFrog - Based on the convenient drag ’n’ drop technique, TaggedFrog allows you to organize your files...
TMSU - TMSU is a tool for tagging your files.