Breguet overcoil, tourbillon, popularizing Breguet numerals, popularizing the use of enamel dials (check out his watches for Turkish collectors), popularizing guilloche for watch dials, popularizing blued steel hands, his natural escapement which led to movements by Daniels, Journe, Voutilainen, Ferrier and more, his movement on the dial side souscription watches which directly inspired watches by Greubel Forsey, Romain Gauthier, etc., some of the very first shock protection, chronograph, and the first wristwatch (on the wrist of a princess). And that's just off the top of my head.