I don't need much, and would like to keep it simple. Just something that will extend the clipboard to hold 2 or more items. I do not want it to write the clipboard contents to non-volatile storage (e.g. hard drive) each time something is copied to the clipboard.
The app shouldn't affect normal operation of the clipboard (using it to copy-paste a single item).
I have a strong preference for portable software, or at least something without and installer.
Must be compatible with windows-7.