I know i know, some people may think leetspeak is a stupid tip, or something just the lame xbox kiddies do, but on the internet, it has it's advantages and uses.. Mostly in the password realm. As word lists for brute force crackers get bigger and bigger, and computers get faster and faster, hackers don't need to spend alot of time getting into your facebook/gmail or even blogger.
this is where leetspeak comes in. all it takes is to change a couple of letters in a phrase, like say christm4str33 and you have yourself a pretty secure password that's easy to remember, or 34st3rbunny, or h4l0w33n. what's cool is that take your girlfriend's name, and change some of the letters into numbers and your password turns from something that'll be on a brute force list somewhere into something that only you know. The cool thing is that it can be anything. your name, your mom's name, your hand's name. your favorite bear. just as long as you remember where you put the numbers. it takes a little getting used to remember where the numbers go, but if you have a system, like just the "a"s or just the vowels. it gets easier to remember. So go forth and speak your inner geek. Be safe out there.