It can be interesting to see the choices different U.S. ex-presidents make in leveraging their public stature to promote causes. Bush Sr. chooses skydiving. Here are some others:Jimmy CarterBill ClintonGeorge W. Bush
(Actually, it's hard to find anything useful he's done since retiring.)
Rain soddens what is kept wrapped up,
But never soddens what is open;
Uncover, then, what is concealed,
Lest it be soddened by the rain.