Is there something which you may find useful in them?
That depends on the model. Not all rubber domes are equal. What do you have?
Key Tronic ErgoForce, BTC dome with slider, older Unix workstation keyboards,
and ergonomically shaped keyboards are some of the more interesting ones.
Some keyboards from the '80s and '90s have high-quality keycaps that are compatible with mechanical switches, so those are in demand for that reason. But don't expect to get any large sums for them.
Notebook keyboards would be interested mostly as spare parts. I believe they tend for wear out faster than desktop keyboards, and they are often more difficult to clean properly.
On the other hand, different collectors are different, and what is hyped up tends to shift with time.
As always with (things that could be) collectibles, it is often a question of finding the right buyer at the right time.
