Did the same recently. Accepted a new position somewhere else and put in my 2 weeks. My company realized that they couldn't find another Mr. McDougal, so they made me an offer to stay. I decided that the devil I knew (that was now offering me more money) was better than the devil I didn't know. Then I had a very awkward exchange with the company whose offer I had accepted.I actually accepted a new job in Denver a few years ago. Then realized I'd have to commute and have FA PTO, so I phoned them back a couple of days later and said thanks, no thanks.