I keep it set at 10 items to limit my exposure if I forget.
I do have to flush the clipboard history after dealing with passwords though. I've found it to be a pretty useful workflow. tap ↓ until desired clipping is selected.LaunchBar keeps a history of your clipboard, so you can copy multiple things using the usual keyboard combo ⌘ - C and then paste them using (for me, I may have changed from the default): Slightly different implementation, but will do what you want:
