In Scotland, it is legal under the Criminal Law (Consolidation) (Scotland) Act 1995 Sec. 49, Sub-sec. 5© to wear a sgian-dubh, or other weapon, as part of any national costume.[6]
In England and Wales, it is legal under the Criminal Justice Act 1988 (section 139)[7] and the Offensive Weapons Act 1996 (section 3 and 4)[8] for someone wearing the national costume of Scotland to carry a sgian-dubh - see knife legislation.
so there you go guys and gals put you kilt on and it's all legal...
http://en.wikipedia.org/wiki/Sgian-dubh:D
Nowhere does it state you have to be scottish...
"Some say the end is near, some say we will see Armageddon soon...
I certainly hope we will, I sure could use a vacation from this silly shit."