well, there aren't any kilts that I know of but there are a few Irish X-Men characters, the Banshee and Black Tom Cassidy, and a lot of stuff went on in Scotland in the onld X-Men tv cartoon.

Also lots of kilts/Celtic stuff in the pc strategy game Medieval: Total War expansion Viking Invasion. Conquer the British Isles as the Vikings, Scots, Picts, Welsh, Irish, Saxons, Mercians, and Northumbrians. I'm addicted right now..