I use the following molds: Sci-fi, Pipes, Gothic and Egyptian, with 1 inch or 1.5 inch floor tiles depending on the game.

1 inch: Star Wars Miniatures and D&D Miniatures
1.5 inch: Space Hulk, AT-43 and HorrorClix

Some of the free-standing structures for the sci-fi line will also be used for Warhammer 40k, and possibly a game or two of GorkaMorka!