Gamma-Ray burst in 775 AD, and we thought a solar flair would be bad.

[SA Friday]

http://news.yahoo.com/space-explosion-blame-tree-ring-mystery-astronomers-205516367.html

Haven't looked into this one, but it would definitely burn out every motherboard exposed to it.

[DOC]

Or turn them into the Hulk. But seriously I wouldn't want to get hit by one.