I don't know the file types of Mesh files but I did a quick search
MeshLab
MeshLab is at Sourceforge and may have something to interest you, you will need to look.
-Mesh
Okay, .obj is a file type?
Mesh Conversion
OpenFoam is mesh-Conversion?
City 3D Models - Free 3D City download
3DM, 3DS, BLEND, C4D, DAE, DDS, FBX, MAX, MB,
MESH, MTL, OBJ, STL, or TGA format
City files
Sci-Fi - Meshes 3D Models | 3D CAD Browser
People > Sci-Fi > Meshes 3D Models
There are different sort fields
Space1999.org - Homage to the "Space: 1999" science fiction series - Free, downloadable 3D CGI models & meshes
Space 1999 mesh gallery
sci fi dropships 3d model
TurboSquid is not free but it may give you some ideas or some demos to play with
Search results for 'scifi' | 3D Models and 3D Software by Daz 3D
Daz3d is a modeling program that gives you a starter program and files for free then you download additional models. I have a large example of the models in the gallery here
3D Sci Fi Models - Download 3D Sci-Fi Models FREE
3D Sci Fi Models -
Download FREE Science Fiction Space Ship, Robot, Sci-Fi Architecture, interior Scenes
SolCommand
200+ free scifi 3D models for download.
Free 3D sci-fi models
To download the Spacejetters sci-fi model collection which includes all of the models below plus many more then
click here.
You can also download some of the Bryce hull materials to use in Bryce 5 (currently free to download from download.com)
Meshfactory - Cinema-quality 3D models in MAX, 3DS, OBJ and Lightwave formats.
www.meshfactory.com
Star Trek Meshes - High quality Star Trek meshes and objects for lightwave and 3D Studio. All free for download. Enterprise, Voyager, DS9, Borg..
www.trekmeshes.ch
2001: A Space Odyssey 3D Models - A superb range of models based on the spaceships that appeared in the Stanley Kubrick film 2001:A Space Odyssey.
www.2001-3d-archive.info
Babylon 5 3D models - A comprehensive index of free Babylon 5 3D models.
www.ultradrive.com/b5_3d_index.htm
Artist 3D - Completely free 3D max models downloads: totaly free 3ds models, 3d art modeling, absolutely free max 3d human models downloads. Digital pictures 3d artists & graphic design software 3ds max studio.
artist-3d.com
123d.com - 3D models assets & news at the 1 2 3D Model Resource Databank - 3D art galleries, 3D tutorials, 3D art features, including Free 3D model downloads.
www.the123d.com
SCIFI-3D
Free Models
The Celestia Motherlode: Home
The Celestia Motherlode is a repository for various addons like textures, models or celestial objects for
Celestia. Celestia is a free, interactive (real-time), 3D astronomy program. It doesn't just show you the sky as it can be seen from earth as most planetarium software does, but allows you to move to and view the universe from any point between the planets and the stars. The Celestia Motherlode hosts over 10 GB of Celestia addons by various creators, which extend or change the way Celestia renders the universe.
All Free as far as I know
http://en.spaceengine.org/load/
I don't know if they have models or not
Orbiter 2016 Space Flight Simulator
I don't know if Orbiter has models or not
Kerbal Space Program – Create and Manage Your Own Space Program
Main Page
http://www.curse.com/ksp-mods/kerbal
Mods Page
Kerbal Space Program
This one simulates a fictional universe, but it's widely hailed as a great educational game about astrophysics.
Construct viable spacecraft that can overcome the effects of gravity and fuel consumption to get your little Kerbals into orbit. Sound easy? It's not.
The position, size and quantity of components you add to your ship will determine whether it reaches the stratosphere or explodes on the scaffold. Timed rocket booster sequences and jettisoning depleted fuel cells are critical to success. Oh, and you'll need to install a parachute to the capsule if you want your Kerbals to survive re-entry.
Well, I hope I listed at least one thing you find interesting