I think the real power of the Internet has been the ability for individuals to work together to voluntarily produce resources that could not be done by themselves. This to me is far more important than being able to pay my bills online.
My No 1 site is Wikipedia.
Wikipedia is amazing. It is a totally free online encylcopedia which is already six times as large as the Encylopedia Britannicia with 326,740 articles. One can find a mine of information on almost any subject, and unlike just Googling for it, this is almost all high quality relevant info. It is amazing that they retain such quality with no overall editors. Anyone can write or edit an article, but there is a way to deal with inaccurate or biased material.
Unlike most encyclopedia’s it also has a lot of reference material on popular culture. So not only can you get a great biography of Gaius Julius Caesar, you can also get a nice overview of what M*A*S*H what all about.
I now visit Wikipedia almost every day and just read a dozen articles or so. if you love always learning new things, you should try it.
No 2 site is Project Gutenberg.
They have put together 12,000 free e-books, mainly older classic texts now in the public domain. A great resource. Want your kid to do more than play games on their computer, download some classical texts. Over time every major literary work could end up here.
No 3 site is epguides.com. They have put together episode guides and summaries for over 2,500 TV shows. Want to refresh your memory about Logan’s Run, or see what happened on the episode of the Soprano’s you missed last night – this is the place.