In fact they are worth several dollars. Which is why many companies worldwide will let you mail them in for recycling. You can even get prepaid (free shipping) envelopes to mail them in.
Folks in the USA who want some cash back can use companies such as:
Also in the USA the warehouse discounter Costco makes it even easier for you! No more excuses now.
No need to go anywhere to drop off cartridges, and no need to pick up the proper mailing envelope.
Just visit the Costco TONER RECYCLING WEBSITE where you can:
1) order a bunch of free postage-paid envelopes
2) print out a pre-paid, pre-addressed shipping sticker (to paste on any envelope you have handy.
Curious about how ink cartridge recycling works?
Find out in this TONER CARTRIDGE RECYCLE BROCHURE put together by the Recycling at Work campaign
You can also learn more from the ENVIROSMART EnviroFacts - Ink Jet and Laser Toner site.