Most workplaces in America don't respond favorably to you dozing off at your desk. But they should; day naps are one of the undisputed great things in the world along with bacon.
And science backs me up on that (about the nap part, I mean). Research has proven that short thirty minute power naps throughout the day help to boost cognitive function and alertness - that means a sharper more productive you. We're not talking about a 2 hour snooze after a heavy lunch - most likely you'll wake up feeling even more groggy after that because sleep is split up into three stages, the third being the deep sleep (REM) that leaves you groggy when you're woken out of it. Power naps should be short, and only to the point where you feel yourself drifting off into a deep sleep, so stage one to two.
ASAP Science explains how to make the most of your power naps in this short video.