Linkedin is one of the top business networking sites and everyone who's anyone is on Linkedin.com. I found the following three great uses of linkedin:
Searching for contacts: I use linkedin more for research than any other function. Whether I'm seeking people who are seeking jobs, or whether I'm looking to connect with the head-honcho of a company; linkedin offers a tremendous value with its search functions.
Answers: The answers section is good if you want to begin creating some relationships with people who are actively networking on Linkedin. Every topic under the sun is available for discussion in the Linkedin Answers section. You can learn about pets, and business plans; mentoring and international laws; Writing and publishing; you get the point! When you respond to answers, you can post a link to your site and information about your company or business. Or you can post a question yourself and get live answers from the various people who have insight into the topic you posted a question in.
Job Search: There are lots of jobs posted on linkedin but the ones that I want to highlight are the jobs that are "exclusive" to linkedin. That means that you get access to a job posting that's not already made the rounds on craigslist, monster, and other job sites.
And you know what? These are all functions that are free to use. That's right, you don't have to sign up for any of their expensive subscription options. Free is good, right? Of all the sites out there, I would say that Linkedin is perhaps the BEST value and the Price is Right at "Free".