Thanks folks!
A good deal of the material I've used is actually pieces from various electrical appliances such as printers, phones and other things that I've chopped up. In adddition, I can say for a fact that I used:
Pieces of Matchbox cars
Armour parts from 1/35 scale Tamiya kits
A cable clip from a bicycle
The trigger to a weed whacker
Half of the swivel-ball portion of an adjustable fawcet
A valve from a coffee maker
A piece of a plastic coat hanger
1/72 scale drop tanks from a Hasegawa model
Surgical tubing
The rocks are cast plaster, using commerical molds
There's other bits too that aren't immediately identifiable, as they were broken pieces that my friends gave me some while ago.
I don't have a shot of this particular piece in progress, but I do have a picture of a previous one in this series before painting:
Here it is primed:
And then painted:
