Los Angeles is full of fantastic historic houses the you can go tour, so if you have a free day, touring a fabulous house is something fun to do!
Here are my top pics:
Gamble House (Greene + Greene)
Hollyhock House (Frank Lloyd Wright)
Neutra VDL (Richard Neutra)
Schindler House (Rudolph Schindler)
Stahl House (Pierre Koenig)