When we went to Lake Myvatn (if that's how you spell it) we were warned that it is the world epicentre of midges. It is. Swarms of them attack you in waves. They get everywhere. No place to hide. A seller sits outside the bus drop-off points and sells head nets. They were great. Makes you look a p****, but seeing that everyone eventually buys them you don't notice.
I used it at home when camping on Eigg, Rum, Jura, Colonsay etc etc and I wouldn't be without it now. Always in my rucksack once I go north.