Just finished that myself. 6 weeks into the new job. Gave the old boss 'informal' 4 weeks advance notice of the formal 2 weeks so that we could transition everything neatly. Not that the megacorp that I left gave a shit, in fact they're probably pleased because I cost a *lot* more than the Indians/Chinese/[select low cost location] people that they'll eventually replace me with, but making life easier for a boss that really did try despite the crap handed down from on high didn't cost me anything. The destination company were fully at ease with that stance as well. Also means I can be a lot more relaxed about it - which is important to me. I'm just not enough of a bastard to screw people over for minor reasons. Probably explains why I have no interest in climbing a company career ladder,