When law enforcement comes calling, it seems that many internet companies, such as RIM, Facebook, Google, and Twitter, are increasingly handing over your personal information as the private information they gather is highly useful.

“When the possibility exists for information to be obtained that wasn’t possible before, it’s entirely understandable that law enforcement is interested,” Google’s Chief Internet Evangelist Vint Cerf told Reuters in an interview.

“Then the issue would be, what’s the right policy? And that, or course, engenders a lot of debate,” said Cerf, who is recognized as one of the “fathers of the Internet” for his early work in areas including communications protocols and email.

Demands from governments for Internet companies to hand over user information have become routine, according to online privacy researcher and activist Christopher Soghoian, who makes extensive use of freedom-of-information requests in his work.

“Every decent-sized U.S. telecoms and Internet company has a team that does nothing but respond to requests for information,” Soghoian told Reuters in an interview.

With many governments increasing the time that companies have to keep this private information, it won’t be long before everything about you is stored with them, making investigations by law enforcement that much easier.

The ease and cost of surveillance are at an all-time low, Soghoian said, with Google charging an administrative fee of $25 to hand over data, Yahoo charging $20, and Microsoft and Facebook providing data for free.

“Now, one police officer from the comfort of their desk can track 20, 30, 50 people all through Web interfaces provided by mobile companies and cloud computing companies,” he said.

“The marginal cost of surveilling one more person is now essentially approaching zero.”

With these fees becoming negligible, expect the requests to start happening more often. If you’d like to understand this a little better, the video below from DEFCON 18 will help you.