[jodrellblank]

Windows 10 has that built in (search for "save multiple clipboard items" in the start menu), and third party ones have been available for at least 19 years (ArsClip - http://www.joejoesoft.com/vcms/97/ )

Surely they have also been available on mac and Linux for as long? Can it possibly have been a good investment to write your own?

[BitwiseFool]

I had no idea this existed, thank you for sharing. As far as an investment of time goes, I just saw this as a challenge and I enjoyed working on it.