Did you know Google often replaces it's logo with a super cool image or game to celebrate important events and anniversaries?  If you visit Google everyday you'd have surely noticed the odd awesome graphic, illustration or game in the place of the usual logo.  They've been doing it for over 10 years now so you can imagine that there's been some amazing examples in that time, and we've collected 10 of the best here!  There's a guitar you can actually play, an interactive haunted house, a Rubik's Cube that's as difficult as in real life, and awesome graphics featuring everything from LEGO to Sesame Street.