Raspberry Pi is still supporting its earliest boards, which dates back 13 years, and can be used for certain functions.
The 2013 Special Edition Raspberry Pi is now slow, however it still has its uses such as a headless machine for specific tasks.
This old single board computer is useful for Linux-based projects, but it will never win any speed prizes and some projects are now starting to abandon 32-bit builds.
One use for the Raspberry Pi 1 is as a pihole for a local network.
Another user has set up several old Raspberry Pi models for school children in Africa to learn about computing. The only issue was finding old hardware to connect to the machines.