The 50 states (+DC) redrawn such that no metropolitan area crosses state lines
Methodology: I used Designated Market Areas (DMAs) as opposed to Census-defined metropolitan areas, as the Census-defined areas are non-contiguous and somewhat arbitrary (and also made for a far less interesting map when I tried using them initially). For those unfamiliar with DMAs, you can think of them as clusters of counties that all share the same local news stations. As such, they are a good bit broader than Census Metropolitan Statistical Areas (MSAs) and generally each incorporate several MSAs as well as non-urban areas. Each “new” state is made up of all counties that make up its DMAs, with the multi-state DMAs being given to the principal city within the DMA.
There are three notable exceptions, as this methodology, strictly followed, eliminates the states of New Hampshire (would be split up between Maine, Massachusetts, and Vermont), New Jersey (would be split up between New York and Pennsylvania), and Delaware (would be split up between Maryland and Pennsylvania). Therefore, in order to “preserve” the 50 states as they currently exist, Portland, Maine, has been relocated to New Hampshire, Philadelphia has been relocated to New Jersey, and Salisbury, Maryland, has been relocated to Delaware. I treated Washington, DC, as a state, so it now incorporates the entire Washington metropolitan area. Wyoming was also a bit tricky, with its two regions (Cheyenne and Casper) being non-contiguous and Cheyenne itself being an enclave within the Denver region. So, some editorial decisions were made there. The last caveat is that the Paducah, Kentucky, region was separated from the rest of Kentucky by the intervening Evansville, Indiana, region, and was thus given to Missouri, which is home to Cape Girardeau, the second principal city in the region.