How can I dispose of my old smoke alarms?

The Office of the State Fire Marshal recommends two ways to dispose of your old smoke alarms:
 
You can legally dispose of your ionization smoke alarm in the garbage; however, you should remove the battery and recycle it.

or

You can return your smoke alarm to the manufacturer. When sending back a smoke alarm, remove the battery and recycle it but do NOT dissemble the smoke alarm in any way. Include a note that states the smoke alarm is intended for disposal. The smoke alarm should be returned to the manufacturer by UPS ground mail (not airmail).