Some of Les Forrester's photography. More at Face On Images

1)Bruegel- The Peasant Dance
2)Titian- Venus of Urbino
3)Caravaggio- St. Jerome
4)Mategna- Dead Christ
5)Botticelli- Birth of Venus

The Pinhole Gallery- A gallery of pinhole photographs by various photographers
Photo.net- A really large website with a lot of really cool photos in the gallery
ephotozine- A UK online photo magazine
National Geographic Photography- I really love National Geographic photographs. Period. This site makes me happy.
A History of Photography- A one man photography Wikipedia-esque site. Not a well laid out site, but will definitely inform you about the history of photography