To put it a little less cynically (those who take care of their image at the office are not always 'yes men'), look at making sure that your accomplishments are recognized as part of your job.

If you write a bunch of code but don't test it before shipping, it doesn't matter how hard you worked on it -- if it's got a ton of bugs, you can't really expect a pat on the back.

Similarly, if you accomplish stuff for the company and nobody knows, what credit can you expect for it?