Hammer is very much like having your entire filesystem in git.

https://www.dragonflybsd.org/hammer/

"HAMMER retains a fine-grained history. The state of the filesystem can be accessed live on 30-60 second boundaries without having to make explicit snapshots, up to a configurable fine-grained retention time.

A convenient undo command is provided for single-file history, diffs, and extractions. Snapshots may be used to access entire directory trees."

edit:

Just now, 10 minutes after posting this, I regretted deleting a file (cabal.sandbox.config) and was able to restore it:

    > rm cabal.sandbox.config // oops
    > undo -i cabal.sandbox.config
    cabal.sandbox.config: ITERATE ENTIRE HISTORY
	    0x000000010bf2e940 17-Apr-2015 06:50:48
	    0x0000000112282990 18-Apr-2015 20:36:53
    > undo -t 0x0000000112282990 -o cabal.sandbox.config cabal.sandbox.config

On Plan 9, the Fossil file system, almost invariably paired with the Venti archival storage server, do precisely that: http://man.cat-v.org/plan_9/4/fossil

You could replace rm with an alias to small script, e.g. mv to ~/.trash rather than deleting the target. The trash can be auto-cleared based on space constraints or after a certain time.

Sadly, the local system is only a small part of what you can screw up. It becomes the undo-email problem pretty quickly.

ZFS