What is the proper way to dispose of old tubes?

Where I live, there are special garbage depots in the city where items containing toxic wastes can be dropped off rather than simply disposed of in the regular garbage. Does your city use recylcing boxes and have recycling pick-up along with regular garbage? If so, the information on garbage pick up at your city's website would contain information as to how to dispose of household items like batteries, CFL lightbulbs, etc.

Jimjoyce and everyone else,
I would love to have your old tubes as long as they are not cracked. If you'd like to send them to me, please email me for my address.
Thanks!

Crazy former Philadelphia Eagles linebacker Tim Rossovitch used to eat light bulbs and other forms of glass http://www.badfads.com/pages/events/glasseating.html He'd probably be a good way to dispose of old tubes.

For what it's worth, he used to also drink down quarts of motor oil, in case the subject of how to dispose of your engine fluids comes up...

Sell them on ebay.

There is a small amount of barium or strontium oxide in many tubes. Barium oxide is quite hydroscopic and the compound does not last long in the environment (according to info on the Eco-usa.net website.) So if you were to inhale or eat newly opened vacuum tubes, there is potential exposure to a hazardous compound. But in reality, it seems this is a case of Quixote like "tilting at windmills." There is a relatively high level of barium in certain foods we eat and there is barium naturally occurring in some water supplies, so it's not as if the stuff is like polonium.