Unidentified cubicle smells

Cubicles are like airplanes. You can never avoid smelling the lunch of your neighbor, and you just pray that your seat doesn’t have a funk when you get there in the morning.
So, my heart went out to Faith over at Frighteningly Uncommon Sense when she recently wrote the following:
It smells like a ham sandwich at my desk today. I can’t trace it to anything, and it’s really starting to bother me.
Unidentified smells are a nasty side effect of lunches eaten at desks and forgotten leftovers from birthday parties, client meetings and communal kitchen cast-a-ways.