I gave my two weeks notice last week.
My job had promised me a raise that would have nearly doubled my pay and gotten me up to market average. Then when it was due, they gave me half and promised the other half would happen in April. April came around and I was told that I would not get the rest because 1) I already got a huge raise (counted as a % of previous salary instead of compared to market) and 2) I lacked qualifications and certifications. Sorry, budget, blah di blah di blah, but hey, maybe next year. I let them know that I was not happy and would be looking.
I am a knowledge worker in an insanely hot field, so I set my LinkedIn to “Open to Finding a New Job” and my inbox exploded. The second company to get to a third interview beat what my current company had promised and is all-around an awesome opportunity. My department is now fucked. I hold 80% of the team's certifications in an area they've been trying to build up. Now they can build it without my unqualified ass.