Linden Endowment for the Arts
If you have never had a chance to search these out its something I can spend hours doing. going through the sims looking at all the art that is created in SL and then put on the LEA Sims if they are accepted for display. You can find these sims by just searching LEA and generally the sims are numbered like LEA1
The above pictures are done on LEA1 and it honestly took me a long time to walk around and take in everything that was displayed by various artists.