What newspaper strip could be a series?

Yes, you have things like Dilbert that try to eek out enough jokes to fill in half an hour, but then you have shows that capture and sometimes exceed their newspaper counterparts.  Garfield brings more personality than its tired counterpart, and Dennis the Menace creates a backdrop that could never fit in a single panel (albeit for kids only).  So what strips could be fully animated, even if they were microseries like 5-15 minutes each if half an hour was too long? 

Doonesbury? 

The Phantom or Mandrake the Magician