If you're beginning to explore the idea of working for one of those consulting firms that advertise heavily in the classified pages, take the time to learn how computer contracting works before you sign anything! Many of these companies will tell you, "We're not a body shop!" and back this up by telling you that they pay their consultants a salary, rather than an hourly rate, and pay benefits. Many will also claim to give their contractors expensive training.
Well, guess what! One hallmark of a body shop is that it tries to get all the contractors it hires working on a W-2 salaried basis--and pockets the lion's share of the hourly rate billed clients. A good consulting firm should offer the consultant the opportunity to work for a high hourly rate--often twice what salaried body shop consultants earn. With that kind of money coming in, you can afford to buy your own benefits.
As a salaried body shop contractor, you'll have no say about which contracts you work on and may get stuck in long-term dead end projects which give you no opportunity to use your technical skills or to add to them. The training that was dangled in front of you often turns out to be fictional, cheap, or scheduled at times when you can't attend. And if the company cannot place you on a new assignment, the "job security" they touted at your interview will dissappear in the length of time it takes to type up a pink slip.
You almost always do best when working with consulting firms--body shops or not--when you make it clear you will work only on a project-to-project basis. When you do this, you only work on projects that interest you. And this way, for each assignment you negotiate an hourly rate that reflects the skills involved and the value that the assignment has for maintaining or improving your contracting skill set.