Green Dragon Inn

A further Tolkien allusion placed in the Blue Book by Dr. Holmes is the name of the inn in Portown in the Sample Dungeon:

"At the Green Dragon Inn, the players of the game gather their characters for an assault on the fabulous passages beneath the ruined Wizards' tower" (pg 41).  

This name comes from the one in the Shire in The Lord of the Rings, which also independently inspired a Green Dragon in Greyhawk City owned by Robilar (PC of Rob Kuntz). According to Wikipedia, Green Dragon is "a popular name for public house in England and Wales". For example, see the screenshot above grabbed from Google Images.

Dr. Holmes later used the Green Dragon in one of his Boinger and Zereth stories (The Sorceror's Jewel, Dragon #46, February 1981), where the inn is the residence of the heroes. Several events take place at the inn. In the beginning of the novel Maze of Peril (1986), a prequel to the earlier short stories, Boinger and Zereth meet for the first time at the Green Dragon. Boinger and companions hire Zereth to accompany them while exploring a newly discovered entrance to the ancient Underworld. The town in Maze of Peril, Caladan, is similar but not identical in detail to Portown.

Finally, in his 1981 book on FRPGs, Dr. Holmes refers to a "player character sitting in the Green Dragon Inn or the Spaceport Cantina does not overlook a slighting remark from the cat-man at the next table. His hand drops to the hilt of his well-worn broadsword, or the handle of his laser pistol. "When you say that, stranger, smile so your whiskers stick out!""

See also: 

Green Dragon Inn Part II, where I look into the history of the Green Dragon Inn in Greyhawk.

Green Dragon Miniature, painted by Holmes