My favorites are so many, and one artist may have multiple paintings that really connect or provide communion (even to other worlds in some cases). So normally I just sample some of the artists by category of the artist's name:
Jan Vermeer sample
Raja Ravi Varma sample
Victor Moscoso sample
overprint 1
overprint 2
unseparated overprint 3
Hans Holbein the Younger sample
Pieter Bruegel the Elder sample
John Everett Millais sample
John Everett Millais sample 2
Edward Coley Burne-Jones sample
Gerard Terborch sample
... that's enough for now
Jan Vermeer sample
Raja Ravi Varma sample
Victor Moscoso sample
overprint 1
overprint 2
unseparated overprint 3
Hans Holbein the Younger sample
Pieter Bruegel the Elder sample
John Everett Millais sample
John Everett Millais sample 2
Edward Coley Burne-Jones sample
Gerard Terborch sample
... that's enough for now