Detectorist John Kvanli is the chairman of Rygene detektorklubb and one of Norway's most prominent proponents of collaboration between amateurs and professionals in field archaeology. Of course he has a tattoo! It's an Urnes brooch from c. AD 1100, in the final exquisite Christian style of Scandinavian animal art.
John tells me he has found several fragments of these fragile objects, but the one inked onto his upper right arm is a settlement excavation find from Lindholm Høje, across the fjord from Aalborg in northern Jutland. The needlework was done by the Martin Tattoo Studio in Bangkok, Thailand.