US Highway 14 is one of several US Highways traversing the State of Wisconsin, although it has only one "Business" routing branching off its main line, in Janesville. The route is marked with an interesting array of signs, some of them the common "Business US-14" signs, and some other odd varieties as shown below. Also interesting is the "City" designation used through much of the city of Janesville.
Chris Bessert, on Wisconsin Highways^, notes the following about City US-14:
BUS US-14 (CITY US-14) - Janesville. A locally-designated and maintained BUS (or CITY) US-14 routing exists through downtown Janesville, however it is unclear how long this route will remain as it is not signed from its parent route, nor do any signs exist outside of the city to direct motorists. Essentially, this is a forgotten-about route which will likely pass into history soon.
My June 2006 trip to Janesville confirmed that the Business route west of downtown is signed all the way from US-14 itself. 
A little more nosing around in early September 2006 revealed several Business US-14 signs in downtown Janesville, though signage at some of the turns seemed to be missing. (No pictures were taken this time, unfortunately.) So I'll have to investigate further the next time I'm out that way...
This sign stands along US-14 west of the City of Janesville to direct motorists to the Business route of US-14 through the city. Mark W. Hintz photo, 6/27/2006, Janesville WI
In the Town of Janesville, Business 14 pairs with CTH-E, although it is marked as "Business WIS-14". This particular sign faces eastbound traffic as it turns onto the Business route from US-14. Mark W. Hintz photo, 12/26/2005, Janesville WI
By far my favorite of the Business/City US-14 signs is this yellow-colored sign, facing eastbound traffic just beyond the split into one-way streets. Mark W. Hintz photo, 12/26/2005, Janesville WI
This City US-14 sign is just to the west of US-51. From the type of sign used, I would guess that it was put here in the 1960s. Mark W. Hintz photo, 12/26/2005, Janesville WI