Goodwill has a clearance center in Houston off Beltway 8 and Hammerly, which is also their central warehouse. The items are priced very cheap, but items are not sold by weight. The store is also fairly small.
For general small items, there are about a dozen ping pong sized tables with plastic bins on them full of the items. Every so often, they clear all the bins off the oldest table (all of the remaining items are thrown away) and put out new bins. Only when all of the bins are placed on the table, may you begin digging through the bins.
This is where I got the VCR that ate tapes ($2), and a full boxed copy of Mac OS 9 (25¢). I think the OS 9 was from before they started ComputerWorks though.
For clothes, they have several tables where they just heap on the clothes. Women stand around the table and dig through the mass of cloth, filling up their shopping carts, which are all invariably stolen from other stores. They will let clothes sit out all day before they pick up all of the remains and either send them to a 3rd world country or shred them up.
Before ComputerWorks, they used to hold computer auctions at this location. Now the computers are crushed.