Some ideas for improvements to the default clipboard functionality:
1. When you right-click, instead of just saying "Paste", it should tell you explicitly what is on the clipboard. "Paste 'Here is some text in a ...'"
For non-text content, it might say something like "Paste image from Ubuntu Brainstorm - Mozil..."
2. There should be more than one Paste command, showing the last few things you copied, like a clipboard manager:
Cut
Copy
Paste "Submit the idea you wan..."
Paste "The Ubuntu community ha..."
Paste history >
Two or three is probably fine for most people. The top option will be the last thing you copied, so it will still behave like a typical cut and paste. The last "Paste history..." or something similar ("Clipboard history"?) would then pop-out a sub-menu with a much longer list.
See the mock-up here.
3. It should be persistent even through reboots.
This way you don't have to worry about data loss through accidentally overwriting the clipboard or otherwise clearing it before you had a chance to paste something that was cut.
I've realized that when I'm doing a lot of things at once, my awareness of what's in the clipboard at any given moment makes me slightly persistently anxious, since I have to mentally keep track of whether I left something in this invisible area of the computer, remember what I put in it, and remember to paste things before overwriting them. :) This should be something that is handled by the computer, not by our brains. It should be impossible to lose data, and the data that's currently in the clipboard should be clearly visible, not left up to our own memory.