It's funny you
> should mention the lawn mowing experience --- I've had the same
> results!  Weird, eh?
Not that weird. Migraines are a vascular problem (blood vessels dilate too
much) so anything that will change the blood flow will also help.  Caffeine,
exercise and ice will all help to constrict blood vessels. Also try ice on
the head and feet to change the blood flow.
I used to have lots of migraines also (at least one a month - don't forget
female hormones are involved also) and now get them about 2 times a year.