As far as of my knowledge goes, keyboard don't store keystrokes in their memory by default (excluding those bundled with keyloggers). The thing that comes to my mind though is that some keyboards do have some built-in memory for storing user's preferences (e.g. gaming keyboards). Can this be somehow reprogrammed to store other data than just LEDs color combo?
Can I sell my keyboard without worrying that new owner might recover previous input in some way?