After many years (decades?) without experiencing the "classic" migraine aura/hallucinations ("fortification illusion"), this morning I had one! --- small blind spot half a degree or so to the lower-right of the center of the visual field ... which developed a glowing zig-zag edge and slowly grew larger over 20 minutes or so, then faded out. (That's where I am right now, as I type this. Fascinating brain phenomenon!)
I took 2 acetaminophen (extra-strength generic Tylenol) and drank a cup of caffeine coffee as soon as I noticed the vision developing, in hopes that that will preempt the actual migraine headache --- we shall see if it works or not!
-- MarkZimmermann 2008-05-10 15:03 UTC
P.S. thankfully, as of the next morning at least, no headache ... maybe I wasn't going to get one, or maybe the caffeine+acetaminophen+hydration worked ... ^z