Flickr
You'll find yourself taking pictures with certain people in mind, or you'll find yourself anticipating the note you'll write on top of the picture!
- Twitter / Twittervision
You'll start to think in short, pithy phrases about where you are and what you are doing.
 - VoIP Info
Realize that phone companies actually do suck, and that there are better, free tools out there that can change the way we communicate.
 - GMail
Stop thinking about folders and hierarchies, and more about searches.
 - Basecamp
You'll start to get really excited about checking things off!
 - Google Earth
Start to think in three dimensions about your city.
 - Blogger
You'll realize that blogging isn't as complicated as it's made out to be.
 - del.icio.us
Create your own mental taxonomy. - Wikipedia
Information is free, and anyone can be an expert!
 
Are there any other sites that have changed the way 
you think?