There is a video that has been circulating online for the past few months that shows different Google "hacks" that you can do. These are all pretty harmless but they are cool to try out on your own. Most of these involve the "I'm Feeling Lucky" button that I don't think anyone in their right mind ever uses.
    First one, type in "google l33t" and click I'm Feeling Lucky. The screen will automatically swap all english words with that letter/number nerd nomenclature. It's called "Google H4x0r" and you can use all of Google's search features in this mode.
    Next up is Google Loco. This one is super easy. Just type in "google loco" and hit I'm Feeling Lucky. The google homepage reappears except now its says Google Loco with the letters moving up and down.
    This next one isn't even a hack, its more of an Easter Egg that the programmers put in. Type in"answer to life, the universe, and everything" and just hit Google Search (not I'm Feeling Lucky) Google's trusty calculator gives you the answer to all of that stuff. Its 42.

For more fun try these:
Type in "google gothic" and hit I'm Feeling Lucky
Type in "ewmew fudd" and hit I'm Feeling Lucky
Type in "xx-klingon" and hit I'm Feeling Lucky
Type in "xx-piglatin" and hit I'm Feeling Lucky

Check out this video to see more Google Hacks.