Lots of people. Common weapon of mercenaries and bounty hunters. My personal favorite would be the commando droids using vibro-swords. They weren't favored against Lightsaber wielding opponents because even if you can parry the blade, the feedback to the vibroblades resonater often had explosive consequences.

tons of people, Boba Fett, Dirge, various Imperial Officers, even Chewbacca used one at some point.