[Searched words]
filter a git log
filter log output command line
grep git history
git view commit
git re-apply commit

To do a simple search through Git's commit messages (another reason to write useful information when committing!) *and* the accompanying diffs, you can use to search for dgd7.org:

git log -Sdgd7.org

Shows us, as one of a few matches:

commit 89bec60d085839fff22fdd4e387063717282edc6
Author: Benjamin
Date: Tue Jun 15 19:47:23 2010 -0400