Well if we are going to include Norway then how about the Krag-Jorgensen rifle. Wasn't as practical as the american military hoped it would be, but a damn smooth action that is still used today in speed matches.
The vikings had an impact on humanity which may be a positive or negative contribution depending on how a person views them. Their human sacrifice and worship did not survive however they scattered their seed worldwide. Many people alive today are decendants of this seed sowing and would not be here otherwise.