Similarly, the hidden emoticons in Skype's chat tools probably won't be apparent to everyone – but if you find yourself in a conversation where you're being told too much information, try typing '(tmi)' and see what happens.

If hidden games are more your thing, there's a copy of Tetris in the uTorrent bittorrent client, and Space Invaders is hidden inside OpenOffice. To play, open a new spreadsheet and add this formula to a cell: '=game()'. The cell will be filled with the text 'Say what?'. In an adjacent cell, type '=GAME("StarWars")' for a quick bout of mindless alien destruction.

Google's new browser, Chrome, also includes an Easter egg – but only if you're using Windows XP. It's triggered by typing an 'about' request into the toolbar – type 'about:internet' to launch the Windows Pipes screensaver inside the browser.