I have no idea what to do with LinkedIn. I have an account there. I think I posted that I work here. Otherwise, I really don't get it, but for what its worth, The Week looks at the significant number of people on LinkedIn, some of whom must be getting something out of it:

100 million
Number of LinkedIn users

98,425
The height, in feet, of a hypothetical stack of business cards representing all 100 million LinkedIn members

44 million
Number of LinkedIn users in the U.S.

200
Number of countries with LinkedIn users

428 percent
Growth over the last year in LinkedIn users from Brazil

178 percent
Growth over the last year in LinkedIn users from Mexico

1 million
Number of users joining LinkedIn every week

20 percent
Share of LinkedIn users who are in the service industry

9 percent
Share of LinkedIn users in the high-tech sector. Members in the finance sector represent the same share.

500
Number of Fortune 500 companies with executives on LinkedIn

997,000
Number of teachers with LinkedIn accounts

1,030
Number of chocolatiers with LinkedIn accounts

74
Number of Elvis tribute artists with LinkedIn accounts

46
Number of LinkedIn users who list "beatboxer" as their profession

4
Number of LinkedIn users who list "dog or cat psychologist" as their profession

1
Number of LinkedIn users who list "martini whisperer" as their profession

8 years
Amount of time LinkedIn has been in operation. The company launched in May 2003.

$243 million
LinkedIn's total revenue in 2010. It makes money from recruitment and marketing services and premium subscriptions.

$15.4 million
LinkedIn's net income in 2010

$175 million
Estimated value of LinkedIn, as submitted in its January 2011 filing with the SEC