Arcade games are what got me into emulation in the late 90s. I would occasionally search the web for ways to play pacman, until eventually I found a few arcade emulators. Then I found a group on irc and followed every new release of mame for several years. They had a release every week and you could count on at least one big hit added, usually a few. I was barely interested in other emulators until pretty much every arcade game I heard of was in game.
Now I have too many handheld. My current favorite is the Powkiddy RGB30, and I am waiting for the Miyoo Flip to come out.