Consider taking a different approach to your next networking event.  Instead of attending with the purpose of trying to make a connection that helps you, how about focusing on making a connection that will help someone else?  As you listen to someone's description of what they do, ask yourself if you know anyone that could help this person.  Write the name of a contact down for them, or offer to send an introductory e-mail to open the conversation.  As you continue to mingle, try and make connections between people you are meeting.  If you really listen to what people are explaining, you will realize there are people who can help each other right there.

Being known as someone willing to help others, who appears confident enough to offer help for nothing in return, and who is well connected, means you will be kept in the loop of the goings on not only within your own career, but within those of others.  It also means that people will remember you and return the favor at some point in your future, long after that single networking event.  And last, but perhaps most important, it feels really good to see a project or career take off because of a connection you helped create!