The next modern streetcar to open will be the South Lake Union Line in Seattle. Currently under construction, it was the brainchild of land owners in the South Lake Union neighborhood that would allow them to connect up an underutilized industrial properties that could be redeveloped with downtown. The downtown end consists of connections to the new regional light rail, monorail and buses.
Most of it is going to be paid for by the landowners taxing themselves. Paul Allen, former Microsoft exec, and the other owners plan to change the neighborhood with high rise apartments and biomedical research facilities. It will be an impressive transformation and they are relying on the streetcar pretty heavily. The idea was conceived based on the success of Portland, so hopefully they will match the experience there.