Jean Snow has a post on gaffer tape signs:
When I went to and came back from Narita airport last week for my trip to Taipei, I passed through Nippori station, where I spotted plenty of great gaffer tape signs (the station is currently undergoing major renovations). I’m guessing it was done by Shuetsu Sato, who is famous for his previous tape signs at Shinjuku Station.
Go to the original post to see photos.