I collect used machinery cheap from internet auctions and place them in the equipment graveyard behind the bush untill i have time to work on the project i bought it for... but usually parts and steel tubes are borrowed off it for everyday jobs before i find time to use it for the project i bought it for...
since i have a band saw i throw very little steel away, i saw small endcaps for tubing from cold rolled C profile leftovers.
I have a small scrap bin close to the saw, it is filled with everything shorter than a 2 feet. When i haul scrap to the trader about 15 km away from here,(which pays 14 eurocents per kilo at the moment) i turn the scrapbin upside down in the trailer, then put all the parts worth keeping, back into the same scrapbin.
Main advantage for me is that i can get an overview of what i have available before i get to throw things away, and i'll allways have some small pieces of different size of steel available without having to saw up good lengths.