[ubuntu-uk] Lock keyboard/mouse without locking screen?

[Andrew Oakley]

I have a two-year old daughter and an Ubuntu laptop (Hardy on a Dell 
Inspiron 1520).

How do I lock the keyboard and mouse without locking the screen? I 
realise this may require installing new packages.

For example, I want to be able to play a video on the laptop, whilst my 
daughter to bashes the keys and clicks the mouse. Ideally the 
keyboard/mouse would only be unlocked once a particularly difficult key 
combination or sequence is pressed.

I don't intend to leave my daughter alone with the laptop (result would 
probably be Ribena spilt over it), but I would like to be able to sit on 
the other side of the room and not have to constantly pull her away from it.

-- 
Andrew Oakley