There's a lengthy Scottish poem about a man named Tam O'Shanter who goes to some bar to drink and look at beautiful women, against the wishes of his wife Kate, and that has its weird little consequences. The poem is in Scottish English, and I had to learn some fifty lines of it by heart on a course on Scottish culture. Then I had to recite it in Scottish English. Hah, memories from last year.
There's a Redwall character, Rakkety Tam. He's a squirrel, and he's the main character of the book Rakkety Tam (of course; the title is his name). In the story, he starts out as a mercenary squirrel, but he becomes the wielder of Martin the Warrior's sword (it's a famous and important sword in that series). In the end, he has to kill an evil wolverine named Gulo. I like the name, if not only because of Rakkety Tam. He was a very enjoyable character.
A famous bearer of this name is Tam Lin in Scottish folklore. Tam Lin was a mortal man who had long ago fallen from his horse and was rescued and captured by the fairy Queen. He feared that he would be made a sacrifice to Hell. He was freed by a woman called Janet, who intercepted the fairy ride at Hallowe'en, and hid Tam Lin in a well.
Usages: Guernésiais
https://en.wikipedia.org/wiki/Tam_Lenfestey
https://fr.wikipedia.org/wiki/Tam_Lenfestey
http://dbooks.bodleian.ox.ac.uk/books/PDFs/590676737.pdf
(Information from name #443483 originally submitted by an anonymous user)