Presented for your edification, following our household's weeklong Cold of Death (which appears to be receding, thank heavens): a method for clearing your head entirely of the icky goo, at least temporarily.
Take a Sudafed or other snot-eradicator of your preference. (I read a chapter of "Atlas Shrugged" aloud while beating a Democrat. Stops the sniveling every time!)
Wait about ten minutes for it to start to kick in.
Eat two huge bowls of really really hot chicken soup. (Or take a long, hot shower.) This liquifies all the snot in your system.
Have one absolutely enormous nose-blow session. Bring lots of Kleenex.
Result: Dry sinuses, snot all gone, two or three hours of blissful unclogged respiration.