When you say threw out I hope you mean given away or at least recycled so they can once be reused. What is wrong with your G5? There are plenty of skilled technicians like eyoungren that could strip a PowerBook G4 down and have it fixed in under an hour or people like me that can rebuild a G5 LCS.
Two logic board failures and possible CPU failure. At the time, repairing it would cost more than it was worth. I still have the dead G5 though but I have no intention on wasting time on it even if the parts are now cheap. I may strip it out and use it to make a table or something once I get my own house. Maybe, I can sell on some parts such as the GPU (ATI 800XT).
I have heard that baking certain G5 motherboards can remidy some problems but for me its just not worth the hassle to attempt to repair it.
As far as I am aware the iMacs were recylced. As people can probably tell, I am not a collector.