I've seen events where they operate three at a time of "the limo", whatever it is. Also the shuffle game with the "Marine One" like helicopters when airborne, etc...
But I'm still a fan of, "They'd be a lot more civilized if we didn't bother getting them any security at all... there's a written succession, and no shortage of politicians who want the job. So, the world can just whack them until they get to one that doesn't tick everyone off..."
Hand them the keys to a Prius and tell them to enjoy driving themselves places... see if the foreign bad guys or their own unrepresented "constituents" get to them first... kinda like a Logan's Run sort of thing. LOL. Let 'em fend for themselves... and they can have a firearm just like anyone else in whatever jurisdiction they happen to be in... and can enjoy getting whatever permits they desire for those, too.
Takes care of a whole lot of problems in one nice budget cut. Secret Service can go back to guarding the Mints, or whatever else they do. Just pull them off the politicians.