I did this. I was teaching, straight after Uni/PGCE and absolutely hated it! Left in a hurry citing my health and anticipated being able to walk straight into another menial job (had savings/no major commitments) with the long term goal of finding a better job on the career path I'd chosen. After a month in the wilderness, as I like to think of it, as I didn't sign on or declare myself unemployed etc. and one or two lazy days in bed, I managed to walk straight into a fairly well payed job in the Civil Service. I was lucky though...
Would I recommend it and would I do it again? Probably not. As my Dad always says, its easier to find work, when you're in work. I think that's how it goes? What I'm trying to say is think about it, don't be rash.