Imagine a typical day — you take the Metro to and from work. You go out to lunch, then maybe run a few errands in the evening, and call people during the day. You swipe your SmarTrip card in and out, and use the Visa for most of your purchases. All throughout the day, you’re leaving clues about your actions and whereabouts. Metrorail knows precisely when and where you get off the train. Your bank can track your location and buying patterns by looking at your purchase history, and the phone company knows who you called, from where, and for how long.

All that is a given — but here’s what should be slightly scary. What do you do at the office all day? Seeing that some people spend more time with MS Word than their spouse, I’m going to assume you’re a heavy Internet user. Now, take a look at some of the more revealing keywords searched for by AOL users. (last year, AOL ‘mistakenly’ released about 2GB worth of queries, all keyed to user ID#s). Some are funny, some are disturbing, and some reveal things that you should not know (warning: not for the easily offended).

Now, these days AOL is only a marginal service with a steadily dwindling subscriber base. How many of you enjoy sharing pictures on flickr, bookmarks on del.icio.us, or use a service from Yahoo, such as news, games or horoscopes? You guessed it — they’re all owned by Yahoo. They’re tracking you.

Take Google — everybody’s beloved, do-no-evil Internet titan. They’ve already come under scrutiny for the amount of user information they collect — and now they want to index your home. Taking my tongue out of my cheek, I google a couple dozen times daily from the Firefox search toolbar. Google Finance is too sexy to live without. I get an increasing amount of tech information (documentation, howtos, etc) from Google Groups. How many of you rely on Google Maps (yay! Google knows where you live), or Gmail (adsense is not magic — they actively sniff your email to serve up contextual ads)?

It may not seem like much at first glance, but all those bits and pieces of correlated user data add up very, very quickly. I’d wager the Internet knows more about you than you do yourself.

Don’t think this information is private to the purveyors of the Internet either — some of the big buzzwords of Web 2.0 are ‘collaboration’ and ’sharing.’ In other words, you’re encouraged to be open and social. Being able to mine someone’s del.icio.us account can tell you a lot about the person, and it’s almost all open to the public. Facebook users should know the dangers of too many incriminating pictures in public. (Remember last year’s uproar over the Facebook news feed?) Sometimes unintentionally public information can be put to sinister uses — you can search for valid credit-card numbers.

All the major Internet players have said they’re very careful about safeguarding user data. I believe them for the most part — what else am I going to do? The Web and Josh Allmann are hopelessly intertwined. I like to think I’m hedging my privacy bets somewhat by using different services — I download email, ad-free, directly to my desktop client. I use Live Local for my mapping needs. (I’m still waiting for drag-and-drop rerouting… hurry up, Microsoft!) I use Yahoo for, uh, horoscopes and stuff. But the reality is, the landscape of the Web is changing before our very eyes — information disclosure is something we’re going to have to get used to.

I do admit — were I in these companies’ shoes, I would have an Orwellian curiosity about that ream of information in my hands. The aggregate statistics coming out of it would be very interesting, at the very least. I’d like to know what they are!