I found out about Berkeley Bowl's "secret menu" when I was looking for beef tendon, which isn't in their butcher case. The butcher recommended that I get "meat scraps," which are just leftover chunks of sinewy, fatty beef. Only $.99/lb, excellent!
Then I was stalking the chow boards and apparently you can get fish heads and frames for $.99 behind the fish counter.
The thing is, I'm too timid to ask what other things they have there - leftover bones from boneless skinless chicken breasts? pork bones? beef bones? Are beef and fish scraps the only things they sell?