The other trick they use is waiting for it to snow and look for roofs where it's melted off. Not so effective here, but can imagine it works well in colder climates.
Slightly O/T but does anyone know how long they have the naming rights for? Will it become simply "Falmer Stadium" at some point? I know some would prefer that, but the Amex name has stuck in my head now.
I think maybe they haven't got round to it yet? There was also something about them not wanting too much branding visible from the road as it could be distracting? I think that might only be at night though, so I guess the new Amex sign might not light up.
I would like to see a little more, but...