One of the greatest gems I got from a blog post once posted back in HN (I can't find it anymore, unfortunately) was about a guy getting a job at Google (or ex-Googler), and he dropped the following (I'm paraphrasing, of course):
> Treat yourself as a business and every job offer as a business deal. Every job offer is a deal, a business deal that must remain carefully balanced win-win. If you let it slip, by getting too much work and not the required promotion or salary bump, it will become a win-lose deal (you on the losing end).