Introduction: Emergency Coffee Filter
I came up with this when I ran out of coffee filters at the office. It's by no means a replacement, but you can woo the tired souls in a panic if they think they're doomed to a day without their caffeine fix with some simple folds in a paper towel.
Make sure that each of the folds is very clean and tight. This will keep the grounds from slipping past little nooks and crannies and ensure a good quality filter, much like the purpose-made ones.