I usually drink a large mug of coffee while at the computer, but not this website. I have some metal detecting boards that I hit first, them come here. Usually, though, I'll eat dinner while I'm browsing this board.
I always tried to be really careful while eating at the computer, as I'm notorious from spilling/dropping liquids and crumbs over the keyboard. I would always shove the keyboard tray into it's fully closed position at the computer desk. When I would type, I'd make sure that the plate of food was well forward of the edge of the desk.
Now, since I just bought a laptop, I don't really eat in front of it as much, mainly because I don't have space to do both where I sit with the laptop, as I'm usually in a recliner.