If you’re aiming at the horror end of science-fiction, 3D Science have a neat free alien. Only it’s actually a very earth-bound bacteriophage, and exists at the microscopic level where it feeds on e.coli bugs. Two .obj files with different poses, plus there’s a low-poly version in the .zip which is 18,000 polys in size. It has many individual elements, so you can dismantle if for parts using 3DXchange and re-build/re-use in iClone if needed.

Free from Fro

Ever wanted a background building to go with your Cartoon Masters character packs? Fro Games has a nice building in a similar style to the Cartoon Masters, as a free .obj/.3ds. 1,200 polys, and it comes with a texture. Fro says… “download and use in any free or commercial product”.

He also has several packs of buildings done in similar style, from $20.