When I was doing installation planning at IBM we did a lot of lightning mitigation (SW Florida).
Grounding and bonding was always the first place to start. We fixed more with a roll of wire than everything else combined. (sounds like an ad from copper.org doesn't it)
My next favorite thing was the ferrite bead. The theory was to shunt out all you could with as short a wire as you could run, then slow down/soften the shot on the signal lines with a ferrite.
