In the East SF Bay area, these folks are legendary: (dating back to NetDay...)
https://www.techexchange.org/  (see "donations" link...)

There are numerous other efforts that take junk computers, refurbish and reuse them in education, community development, etc.

Hi Marianne. 

As a manufacturer, we're trying hard to promote reuse. Here are some of the things we are doing:
 

• We've migrated all of our products to offer a lithium-ion option, with associated protection circuitry, as well as alkaline batteries. We encourage using rechargeable batteries where possible, but still understand that in the field, it's much easier to find alkaline batteries locally.
• We offer an upgrade program for our hardware. We're in the 7th year of having our Boombox devices available and we have a trade-in program where we give a 50% discount for people that trade-in their old boards for the latest version. We then recycle the old boards for internal projects, educational donations, or prototypes of new designs.   
• We've kept the same enclosure across all our designs so it can be reused across upgrades. Unfortunately we can now make our boards much smaller, however keeping the same form factor for the enclosures saves on wasted plastic since they can just remove the old boards and pop the new ones in.
• We've modified the enclosures to last longer internally as well as externally. We hand place brass screw inserts into the enclosure's mounting holes. The stock mounting holes were made of plastic and didn't survive more than 2-3 re-insertions before they became threaded and unable to securely fasten the circuit board down. The brass inserts allow boards to be removed and replaced indefinitely and was one of the main technical improvements that allowed for our upgrade program. 

We're still looking for other ways to reduce waste and make our hardware more sustainable as well.

Hope this helps.

Akiba

also might follow up with these folks:

https://recyclemybattery.org/  

that I think is from this guy:
https://www.ted.com/talks/sri_nihal_tammana_recycle_my_battery_empowering_communities  

there's this guy too:
https://www.youtube.com/watch?v=AZaLLvwwx84  

note Carly has quite a discussion going on rechargeable batteries in this other Wildlabs thread...