When Todd delivers the parts Claudia ordered, Claudia tells him he's a Wonder Twin; Allison Scagliotti recently played Jayna, the female Wonder Twin, on Idol (2009)
Assuming the map in the Warehouse 13 command center is fairly recent, Univille has a population near 3,748.
Opening sequence, 1944, Buck Mendell, Secret Service,from Warehouse 13, full authority, African-American. In 1944 a black soldier was deemed not good enough to die in a white soldier's foxhole. There was little chance of white military guards accepting the authority of a civilian black man waving a badge. FYI: 1956, Charles Gittens, first African-American Secret Service Agent.
The shipping labels on packages 186 A and B list the warehouse as being in Stokes County, SD. In reality, there is no Stokes County in South Dakota. The closest name would be Stanley County which is in the middle of the state.
Pete tells Mika that "Marines don't wear patches". It's true that modern US Marines don't wear unit patches. It wasn't until September 1947 that the Marine Corps abolished the wearing of unit patches. But, it's never determined what era/year the soldiers are allegedly from. If they are from WWII, or older, it's possible they would have had unit patches.