You may know that (in the US) you cannot simply put a used monitor in the trash. It has to be disposed of in an "environmentally approved" manner. This is because of some substances in the CRT that are dangerous to the environment. In our city you call a recycler and actually pay him to come and haul it away. With the popularity of LCD monitors, thousands and thousands of CRT monitors are now being shipped to recyclers. What you may not know....p>What you may not know is that these recyclers are high-tech junk yards for all kinds of computer hardware.. Recently I needed a monitor for a miscellaneous rack in our server room. I went to the recycler and found a 15 inch monitor (it had to be small to fit in the rack) for 10$. The recycler I visit had probably 1500 monitors stacked around slated for disposal, many if not most of them perfectly fine.
And that's not all! I've picked up spare power supplies, extra switches, spare SCSI drives, a server cabinet, a SCSI Controller (ultra 160), PC 100 RAM... and the list goes on. An electronics recycler is like a junk yard for geeks.
Some things to consider. Use your head. Don't build a bunch of production servers from junk picking at the recycler. It's a great choice when you need some non-critical piece of hardware, a spare, or when you are trying to replace a particular item that's hard or expensive to find - like when you have an 8 disk array of 9 gig scsi's, or when you need a particular Cable. It's a little cheaper than eBay and you get to examine the item before you buy.
Most recyclers are NOT techies. They are more like junk men. They sell pallets of PC stuff to people who strip out the gold leads and other usable items and then sell for scrap. They often don't know what you mean and you have to explain your self more thoroughly. The guys I go to don't really know the difference between the various scsi standards - or how valuable and hard to find a server rack and (especially) the rails can be. You have to sort of work with them to find the stuff you want. The good news is, that like typical junk men, they love to bargain and they are happy to let you poke around (mind the rats!).