[blhack]

I tried the headphones thing for a long time, but it would usually result in people just coming over and knocking on my desk until I looked at them.

They'd then give a little polite smile and a "Hey, huh, are you busy? Whatcha doin?"

I feel like a jerk literally shutting the lights off (so they think I'm not here), but it does seem to be working (things are getting done, I mean).

[vbrenny]

Well.. the whole ideia is to give out the message of 'I'm busy'. I have coworkers that use unplugged headphones, just to get the message delivered. Of course, it works only if other people understand this signal.

You can try to use some form of humor to disguise it.. try a little warning sign with something like 'DO NOT DISTURB: Genius doing science'. People will, at least, stop at the sign to take a closer look and you will be aware that they are coming, not scaring you.