Wait a minute! You could get yourself drummed out of this society!
Yes, Roy's horrible story sure made an inpression on me, too, and I will be a LOT more careful about picking up anything that might contain pressurized contents, hazardous or corrosive stuff, etc. Especially here in MO (Meth lab country) you have to be REALLY careful about fire extinguishers, as that is the choice container for stolen anhydrous ammonia, which they don't contain well. (I had a cheap 5 Lb Bernzomatic extinquisher explode in my car (thank goodness I wasn't in it at the time) some years ago. The thing was no thicker than a soda can, and the powder load had eaten halfway through the wall.)
But, that accident won't stop me from picking up interesting gear, once I have determined it is safe, and bringing it home. (I have almost NEVER actually picked something up on the side of the road, mostly from the standpoint of being rear-ended by a drunk while checking the item out.) I DO, however check out the dumpsters at work very frequently, as people throw the most amazing stuff out, as well as put out usable "junk" for the vultures. I've sold several thousand $ of stuff I had no use for, but figured it was worth something on eBay. I also have made some interesting gadgets, got spares for various gear, misc. metal stock, furniture, etc.
My CNC milling machine has a computer monitor/kbd arm, and I got & modified an office chair with a height extension, from this source. My test bench computer is off the loading dock - fully working Pentium 133, which is just fine for what I use it for.
I got a fully operational high vacuum pump (Welch 1402) out of the dumpster. I sold a slightly different model on eBay. I got a diffusion vacuum pump and a huge valve off a vacuum chamber, and sold it on eBay.
I got a very old Nicolet transient digitizer (early version of digital storage oscilloscope) cleaned the faceplate and sold it for $100 on eBay. I got an HP 54200 (I think that's the model #) digital scope out of the dumpster, it works perfectly, so I kept that!
I can't even remember all the other stuff I got, or where I have it hidden!
Jon