For me, its highly detailed scenes/props at reasonable prices. Here at Renderosity, good examples are the product offerings from London224, mostly for Poser and Vue (I have 30+). Another example is Coflek-Gnorg, I have 129 of his (hers?). Beyond Renderosity, a great example is Luigi Marini's Vue scenes, now at CGTrader since Cornucopia3D is dead. His typical price is $12 for vast and detailed scenes, often on sale also. And he is very responsive to questions.