stickman,

The article you read was most likely about Adrian Lamo. He's received a lot of press lately (mostly because he hacked into the New York Times and they decided to press charges) and it's true that he only uses a web browser to find his way into corporate networks. You can read more about his adventures here:

http://www.securityfocus.com/news/6888 - this article illustrates what happens when you engage in illegal activity
http://www.securityfocus.com/news/296 - this is an article about some of his tactics

It's not rocket science, but it is illegal so don't get any ideas . As for your third question "why arent so many crackers hacking using it", the answer is, they are. A web browser is just one of many tools in an attacker's toolbox.

Take care,
_TOMDAQ