In today's tough economy, having numerous options to supply income is almost mandatory, and freelancing has become a safe bet for many Americans.

The number of freelancers has exploded to 21 million. They get their paycheck from a lot of different employers and work by the project, or gig, thus creating a new term, "giganomics".

"You really can replace your income. You can do it," said freelance writer-marketer Karen Swim. "You have to be able to mix it up."

Swim has been going from gig to gig for six years now and earns $100,000 a year. The key she says is spend as much time lining up new gigs as doing them.

Jason Goodrich lost his job as newspaper editor a year and a half ago

"I would come home and say you are not going to reinvent yourself or find a job growing a beard in your pajamas," said Gretchen Goodrich, Jason's wife.

Instead of a full-time job, Goodrich decided to work gig to gig out of an office he shares with other "giggers" for $500 a month. He has already picked up three clients, which feels good. However, there is no insurance, no retirement, and no security.

"The hardest thing is not knowing three months down the road where you're going to be," Goodrich said. "On the other hand, at least it is not boring."