I've got a coworker that just brought in a Sam's Club sized box [literally purchased from there] of Sunflower Seeds to which he's been munching on since last week. *Crunch *Snap *Spit followed by smacking of the lips.

mfg:
Talk about annoying. He's the same guy that literally has to tell me everything that he's doing like as if I want to hear about it all day. Not to mention that at least once a day but typically within an hour after lunch he'll start a conversation with me while standing near my desk then kind of stand there awkwardly as if he can't move, then tell me he's gotta go drop a deuce while scurrying away.
For the most part I throw on my headphones to try and avoid all conversations and drown out his sunflower seeds for the most part but it doesn't always work.