[Catalyst] Cache of unchanging content

[John M. Dlugosz]

  Say I want to use TT in the .css, so (for example) I can name my colors and other 
repeated content easily.

I'm assuming that I can define a Path of some kind on a rule to serve those.  Any recipes 
to share?
More critically, I want the browser to know that it doesn't have to keep re-fetching it on 
every view of every page.  How would I manage that?