Nice post from Crash on TMMB on how to fight a cold/flu:
I choke down as many vitamin C (or, even better, Emergen-C drinks), beta carotene, and echinacea/golden seal pills as I can. This usually kills it within 12 hours; then I take Mucinex to get the mucus out.
I think they only make Mucinex for kids (to be honest, I've never looked for it in the regular cold&flu aisle), but it's a decongenstant that loosens mucus in the chest and actually induces coughing, to help you get the nasties out faster. Otherwise, you can feel great, but still be coughing up strands and strands of mucus for days. Loogies; yum.
Oh, and also - for those of you who are big on taking the spicy food route to rid yourself of excess mucus and congestion - STOP. That is a terrible idea. I know it provides temporary relief, but in the long run, it makes your problem much worse. Capsaicin,* which is the compound in peppers and some other foods that makes them spicy, opens your blood vessels, which is why you seem to feel better - it eases headaches, makes your nose run, gets the mucus out, and can relieve (temporarily!) sinus pressure. However, once the effect wears off, and the capillaries in your now-dry sinuses constrict, your body senses the need to moisturize that very sensitive tissue, and then sends mucus production into overdrive. You'll end up with twice as much boogery mess than you had before you downed all the Texas Pete-laced chili.
*Capsaicin is not found in wasabi, however (the spicy green asian horseradish paste served with sushi), so it's ok to use that to try to turn yourself into a drippy human faucet; you won't get the nasty side effects.