I like the Caillebotte's from post 14 and post 36, the Twachtman's in 16 and 24 (although the 16 is a better painting even though I love the real Emerald pool. God is the best artist of them all), the Monet's in 22 and the two Sloth posted (although the second is better than the first)
The Monet's posted in the article are too formless and dreary to go over the sofa. Likewise the haystack just doesn't catch the eye or the imagination.
It's a pity the old masters never did an Enterprise fighting a Klingon battle cruiser painting. :^)