Dave's - Southside.
Only thing I like better than Dave's in Oakland is the Dave's in the Southside between 12th and 13th on Carson St. The best part is they are open until MIDNIGHT EVERYDAY except Sunday til 8pm. They also carry some used instruments and a ton of used DVDs and VHS on top of the vinyl, CDs and cassettes. I spent a lot of my college hours in this place (day and night) and continue to go there after, especially with parking lot accros the street, something that sucks in Oakland.
With a selection so nice, it's the ultimate used-CD dealer.. Digital CDs are what Dave's specializes in, but there's a decent collection of cassettes in the back. All sorts of categories are represented, from rap to rock to soundtracks to classical. Be sure to check out the New Arrivals bin just to the left of the counter.
Analog Upstairs--that is, upstairs from the upstairs (Dave's is on the second and third floors of the building)--is the vinyl room. You won't find too much up here, but it's always worth browsing.
Cinema Well, yes, it's called "Dave's Music Mine," but there's also a healthy sampling of used movies for sale, in both video and DVD formats. You'll find a lot of old workout tapes and sports blooper collections, but also a good number of rarities and blockbusters, all for under $20.