Classic Century Square

Huge selection, sometimes overpriced. But if you’re willing to hunt, you can definitely get a deal. I found the furniture to be too pricey for what I was looking for (no end tables under $ 100, really?) but I scored a great popcorn popper for $ 4 and picture frame for $ 2. If you’re willing to take the time to comb around, there’s some great stuff. Helpful tip — there’s a nice big parking lot behind the store with its own entrance.

UPDATE: I reviewed this as a VENUE, as a musician; here’s my post-​venue review.
EXCELLENT place to play; DeDe understands what musicians need; they booked us an hour apart so there would be time to load out previous act/​load in; ELEVATOR load-​in and had help from Tory loading in +whatever else you might need help with. Nice crowd; the place was full from top to bottom with vendors and there are chairs & tables in front of the stage. Your music can be heard throughout — stage is on 3d floor and building is open top to bottom. Plenty of outlets, movable velour backdrop, stage large enough and nice, good lighting, encouraged to set up CD sales if you want. No PA yet but they said they are working on it. They run a tight ship and keep acts on track. Easy parking in back (the lot is BIG) and large door +freight elevator load-​in. If you have read this far, you’ll find out that Tory does a backflip a day!

It’s an indoor flea market. Enough said. Packed with stuff, most of it modern, and much of it just leftovers from yard sales.
The building is way cool. Go to see it and the 1950s modern architecture.

The building is very cool just by itself. The stock, like any antique/​thrift/​booth/​consignment store changes constantly and each booth can vary from awesome to garbage scam. You can walk to a half dozen or so other antique malls or thrift stores in just a few minutes along or near Central between Carlisle and San Mateo, a tiny antique district east of Nob Hill.
It just used to be a lot cooler. It was jam-​packed, every floor, constantly shifting and bustling. Now it’s kinda thin, empty, quiet. It used to be the main stop on the thrift crawl, but at this point some of the others nearby have funner or more fairly priced stuff.

Heather C. pretty much hit the nail on the head. This place has a lot of cool stuff to look at, but some of it’s overpriced, as it’s up to the private vendor who owns that booth. My wife found a cool japanese shirt for only a few dollars, and there were old issues of TIME and some vintage military stuff that was very cool. I’d recommend checking this place out if you just want to browse around and kill some time.

My feelings are mixed here. They have some really great stuff, but some of it is grossly overpriced.
To be fair, that is to be expected with any shop that is of the antique mall format, in which numerous people each have their own wares in a booth.
I also imagine that it is largely dependent on what exactly you are looking for, and your own personal tastes. Personally, I love things like junk paintings and old books. This place has no shortage of either.
But in nearly all cases, the things I really like are priced well above their value. This is always a sticking point for me with thrift/​vintage/​antique stores, flea markets and the like. You get these people who think that they are experts on everything, and then price things out according to what they THINK they know, which rarely ever meets the desires or spending habits of the local market.
Sometimes this works in my favor, and I will find something amazing that is gloriously underpriced. Typically it is the opposite scenario though.
Classic Century Square is worth a visit, even if you don’t plan to buy anything though. They have loads of kitschy stuff from ugly (in a good way) hanging light fixtures to fabric to magazines to furniture.
Please note that the best stuff seems to be up on the third floor, which is apparently occupied by just one vendor. That person is rarely there though, and they won’t even let you browse up there when they aren’t. I have been in the store maybe between 5 — 10 times, and only on one of those was I allowed to go up there.