Pro tip: don't share your email address on microblogs
For the seasoned Internet user, that headline is a no-brainer. Unless you're hoping to be spammed ad nauseum by everything from (ahem) stamina enhancers to mail order brides to bogus antivirus software, don't post your real email address anywhere.
Less security and privacy savvy users, however, might not be aware of the pitfalls yet, so here's some advice. If you are using a social site like Twitter or Facebook, don't be so quick to give your personal information away.
For an unsavory soul to harvest your address from Twitter is as simple as setting up a search for a topic like "email me at" - text which CNet found occurred nearly 300 times in a one-hour period. It's worth noting that a good portion of that volume actually comes from Twitter spammers trying to drum up business - but unwary users are doing it, too.
It's bad enough that these people are actively spamming trending topics on Twitter, so don't invite them into your inbox. If you must post an address for people to contact you via email, sign up for a dedicated public email address with service like GMail or Live/Hotmail. That way you don't need to give out your everyday family-and-friends address.
Another option is to familiarize yourself with some sites that provide disposable email addresses like the ones I wrote about a while back. They're a perfect way to let people contact you without the risk of polluting your inbox.