I'd use them, of course. Or stockpile them, as we already have spares on the lamp shelf.
HazMat? Not enough mercury in them for that -- and it isn't released when the bulb quits working, only when it's broken.
I seem to recall something from county recycling about CFLs -- while they'd prefer you turn in dead ones at the recycling centers, it's okay to put them in the trash. (Good thing -- nearest recycling center I know of is 15-20 miles away -- and INTO the city to boot.)
Whoa! What?
Lets say you throw out one CFL , that's 4mg. of mercury, crushed in the back of a garbage truck that drops it's load at a local landfill.
Let's say that you have one thousand neighbours who do the same thing. Now we have 4000mg, or 400g, or 40kg (is my math right?4 kg?) of mercury going into your landfill.Which leaches into the water table, and over a few years what have you got?
Glow in the dark children, that's what you've got.