Ditto is a clipboard manager. It's an extension to the Windows clipboard and stores data in a SQLite database; db is accessible with external tools.
The retention of copied data is configurable (by expiration or by size); it's possible to set specific items to not be auto deleted.
Main interface is callable by configurable shortcuts, and it's possible to have fast shortcuts directly for the first elements.
It can be paired in a group of instances via network to share the clipboard on multiple machines.