Weird things to that you feed your fish

So I was just reading around some forums today and found were somebody used a old Mysis frozen feeding package to freeze bananas in the cube slots. Then they dropped the froze cube bananas in the tank and the tang went crazy for it.

I would be very interested to hear if anybody feeds there fish or inverts, heck anything in the tank with something other than normal food. I have also heard about feeding tangs lettuces and broccoli as well?