This was actually featured on
Good Morning America earlier today.
From my personal experience, I never quit a job until I had another lined up. But if you can make it w/o a job, just put in your 2 weeks notice and let your HR person know you'd like to do an exit interview.
My last job i started to hate more and more every day until the point i got physically sick on Monday mornings and by Friday afternoon I had "i'm gonna go postal" scenarios running through my head... but I made sure to still put in 2 weeks notice AND took a vacation b4 starting the next gig! LOL.
Your health and sanity are SO MUCH MORE IMPORTANT than a job. You have the rest of your life to work.