(This is a guest author article.)

Strange sounding title, isn't it? There are so many "freebies" floating around on the internet right now: web-based e-mail, blog/website hosting services, photo and image sharing communities, video portals, social networking sites, "free" traffic generating tools/widgets and tempting ways to make money without spending anything.

Free services don't run on air and water. They run on powerful servers that need to be constantly upgraded to keep up with the users who sign up because it's "free." And servers, hardware and infrastructure cost money. Only the big companies can absorb the initial investment to make up for it later. And trust me, they do find ways to make up for it later, otherwise they cannot stay in business.

And so when you get something free, you actually pay for it indirectly. Either with advertisements or content which can be used to generate advertisements. By becoming an active user of social networking websites, you provide data (valuable data) to these services which find it extremely useful not for spamming you, but for producing more stats in order to show their advertisers. When hundreds of thousands of users provide them with this data, imagine what they can do. Even their collection of e-mail addresses would be huge! So what about all the other personal data you put on these sites? What about all those millions of personal messages and e-mails stored on these mega corporations' servers? Can you imagine the goldmine of information they're sitting on? All of it might not be useful to them; indeed a huge fraction of it might be junk - but did you consider how much of valuable data resides on google and yahoo servers?

I think what they've successfully done is market the internet as an active, interactive social place rather than just a benign information storehouse which it used to be earlier. The transformation has come about and has been beneficial to the public, but it's not without its costs. A large majority of internet users have no idea of the basics of privacy and security. Take a look at how many people put up (high-resolution) photos of themselves on public websites. I've seen a lot of them even leave behind contact information like telephone or mobile numbers. The fact is, the internet is a very, very public place.

So the next time you feel the urge to join yet another "free" service and share your data with them, consider that it's not really free. You're giving up a lot of valuable (potentially profitable) information to them in the process.