There is a small but cool little barcade off Mills Ave called BART. They regularly rotate their arcade and pinball machines. They offer various craft beers and ciders (bottle only). And they have local art on the walls for sale. There are some cozy couches in the back to hang out on. Usually they not busy during the week (at the time of writing this). They host regular events, including art showings, competitions, game dev meetups, etc.