This is a personal, nifty tool I use together with my MultiMarkDown based text notes. If you want to try it, you're welcome, but it's not my primary intention to make this for anyone but myself.

Usage: kw [-p command] [keyword list...]

Given files which contain rows that begin with "Title:" and "Keywords:", list those files that contain the given keyword[s] in either of those rows.

Options:
-p command    Pipe the output to the
              specified command via
              null terminals and xargs.

Example: kw recipe
Example: kw -p vim recipe