Very useful, needed to run graphical applications as super user
Mint 16 KDE Edition - Attempting to run Update Manager. KDESudo asks for my password. Tells me if I get it wrong (deliberately, just testing!), but more than 90% of the time fails to start Update Manager when I get it right. Eventually, after on average about 20 attempts, for no particular reason, it works. You wouldn't want to be planning something time sensitive!