My preschool daughter gets an occasional fix for Horizon Chase Turbo, an indie arcade racer in the style of Outrun and the Lotus series on Amiga. It’s quite enjoyable, a very nice retro racer that is packed with content.
After that, I have OpenEmu on my desktop Mac, and my go-to games for a quick arcade fix are Pac-Man and Defender for Atari 5200. Gyruss and Montezuma’s Revenge are also endlessly fun and within easy reach.
Update: Oh, completely forgot about Sega Rally, which is back on our regular rotation thanks to the excellent Pandamonium documentary. I've got that wonderful music running through my head. Is this the greatest arcade racing videogame of all time? Quite possibly, although Hydro Thunder, Daytona USA and the first two Wipeouts are also strong contenders.
I've also been playing 5200 Mario Bros "Encore," which is a graphics hack created by a member of the Atari Age forums. It's a terrific makeover that brings the visuals more in line with the arcade original, including the character sprites and stage designs. I love this version because the gameplay flows so nicely, action becomes quite hectic after a few stages, and I have this ability to jump backwards that reminds me of Super Mario 64's razzle-dazzle. This might be my favorite version of the arcade classic.