Tag any file and search by tags

Registered by qbit

I'm looking for years for the ability to tag any file on my HDD and then to search by certain tags. I have no idea at which level can be implemented this or how complicate it is, but I'm seeing this feature as a significant step forward in organizing the files.
If anyone else thinks this is helpful, I'm ready to create a detailed blueprint document for this feature from the user point of view.
P.S. I see an older post in Linux Mint forum on the same subject, but is quite "dead".
http://forum.linuxmint.com/viewtopic.php?f=6&t=28701&start=0

Blueprint information

Status:
Not started
Approver:
None
Priority:
Undefined
Drafter:
None
Direction:
Needs approval
Assignee:
None
Definition:
New
Series goal:
None
Implementation:
Unknown
Milestone target:
None

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