Docs.com can help you visualize data about all your Facebook friends inside a spreadsheet. You get to see your friend mix by gender, by their age group and their current location (city).
This illustration was created in early 2006 using logos of Web 2.0 companies that made headlines or were launched around that time. Obviously, lot of things changed in the last three years - some companies got acquired, some became successful on their own while others went bust.
SizEasy and Pective are free online tools that help you visualize the dimensions of any object (like mobile phones, laptops..) through comparison.
Akamai, a company that handles anywhere between 10-20% of all the web traffic, offers some interesting charts to help anyone visualize traffic on the web in real time.