It's a solved problem. Commits can be represented as e-mails. (e.g. "git format-patch").

The mails can be catenated together into one file; this is called the mbox format.

Get three commits as three separate files:

  $ git checkout
  Your branch is up to date with 'origin/master'.
  $ git format-patch HEAD~3
  0001-Issue-successful-status-out-of-cdlog.recover.patch
  0002-cdalias-take-zero-one-or-two-args.patch
  0003-cdunalias-improve-test-for-undefined-alias.patch

Now checkout to before those commits, detaching HEAD:

  $ git checkout HEAD~3
  Note: checking out 'HEAD~3'.

  You are in 'detached HEAD' state.

  HEAD is now at b3c0288 New feature: auto recovery.

Now, catenate those files together to create one "patch.mbox" file:

  $ cat 000* > patch.mbox

"git am" takes the whole file and applies it:

  $ git am patch.mbox
  Applying: Issue successful status out of cdlog.recover.
  Applying: cdalias: take zero, one or two args.
  Applying: cdunalias: improve test for undefined alias.

Clean up: return to master, delete the file:

  $ git checkout master
  Warning: you are leaving 3 commits behind, not connected to
  any of your branches:
  [ .... ]
  Switched to branch 'master'
  Your branch is up to date with 'origin/master'.
  $ rm patch.mbox