Those I've been to:

• Los Angeles County Museum of Art
• MOCA Los Angeles
• Getty Villa, Malibu
• Getty Villa, Los Angeles
• Huntington Library and Botanical Gardens
• Ventura County Museum
• Santa Barbara Museum of Art
• UCSB Art Museum
• Hammer Museum
• Fowler Museum
• De Young Museum of Art, San Francisco
• Legion of Honor, San Francisco
• San Diego Museum of Art
• Museum of Church History and Art, Salt Lake City
• Philadelphia Museum of Art
• National Gallery, Washington DC

Those that I'd like to see

• The Museum of Modern Art, NYC
• The Metropolitan Museum of Art, NYC
• The Whitney, NYC
• The Louvre, Paris
• Musee D'Orsay, Paris
• any museum in Paris I've missed (which is all of them...)
• The British Museum, London
• Every major art house in Italy, Berlin, Vienna, Prague
• The Vatican collections