It's on espn...
http://sports.espn.go.com/nfl/trainingcamp10/news/story?id=5476849
"Minnesota Vikings wide receiver Percy Harvin was taken to a hospital by ambulance after collapsing at Thursday's practice, and coach Brad Childress said Harvin suffered another migraine headache attack.
Harvin, who has dealt with migraines most of his life, has been unable to practice for most of training camp because of the headaches and their debilitating symptoms."