I'd like to expand on this a little. When networking, don't ask yourself 'What can this person do for me?' ask yourself 'What can I do for this person?'
With regards to networking, don't just focus on people in your or related industries, add good connections from as many fields as you can. You never know when you're going to run into someone who you may be able to help or who 'knows someone'.
Become known as the person that puts people together. Trust me, if you help people, they will remember you.
On one of his podcast episodes, James Altucher mentioned that you should give 1000% to get 100% back. Have an abundance mentality. There is plenty of opportunity to go around for everyone to share. I've forwarded on potential clients to another person on several occasions, because she is a better fit for what those clients were looking for than I am.