Never underestimate the power of good ol' ice. A cold pack can work wonders on headaches.
Excedrin products contain acetominophen but also aspirin and caffeine, both of which can cause a number on the guts, so just keep that in mind.
Ok, so I know they say not to take Advil, but I do anyway. Here's what I do for my migraines (Imitrex does not work for me):
First I take 4 Advil
if no or only mild relief after two hours, 2 Extra Strength Tylenol with a diet soda with caffeine
if still no or only mild relief then 4 more Advil
If necessary, 2 Extra Strength Tylenol after two more hours
Usually I get relief by then.