While it may have never had a physical GR address, David Letterman's oft referred to "home office" was once relocated to Grand Rapids.
On June 12, 1995 during an appearance on Larry King Live, a Grand Rapidian called in and suggested that Letterman make the move from Sioux City, Iowa to Grand Rapids...
David Letterman ended his incredible 33-year run as a late-night host yesterday, and as previously reported, the Foo Fighters were on hand to help him say goodbye.