Using Eagle3D and POV-Ray, you can make realistic 3D renderings of your PCBs. Eagle3D is a script for EAGLE Layout Editor. This will generate a ray tracing file, which will be sent to POV-Ray, which in turn will eventually pop out the finalized image of your PCB.
Step 1: Things You'll Need
-EAGLE Layout Editor -- This is the PCB CAD/CAM program used for making your PCBs. Westfw has some great tutorials on how to make a schematic and turning that into a printed circuit board using EAGLE.
-Eagle3D -- This will generate the file used by POV-Ray
-POV-Ray -- This will render the final image of the PCB.
Step 2: Create a POV-Ray File
After installing the required software, you need to generate a POV file that is read by POV-Ray. To do this, open up your board in EAGLE. Then, click File>Run. You want to find the install directory of Eagle3D, and find where the ULP files are stored (mine were stored at C:\Program Files\Eagle\ULP\Eagle3D). If you are running a version of EAGLE later than 4.1x, you'll want to select 3d41.ulp. If not, select 3d40.ulp. Click Open and a file generation interface should pop up. This is where you will make your selections on how the rendered board will look. I usually leave the settings to their default positions, unless I am using custom created parts. Then click Create POV file and exit. A message should appear telling you that your POV file has been created successfully.
Step 3: Let POV-Ray Include Eagle3D Files
Eagle3D uses special #include files when it is scripting, and you need to give these files to POV-Ray for your image to render. First, go into your Eagle3D program directory. Find the folder named POV-Ray, and copy the files to the "include" folder in the POV-Ray root directory. (Picture 1)
To make life a bit easier, you could also specify the directory where the original Eagle3D include files are located. To do this, open your POV-Ray root directory, open the "renderer" folder, and edit the POV-Ray.ini file. Add the following line to the base of the file:
Of course, you should change the "C:\Program Files\Eagle3D" to where ever the root directory of Eagle3D is located. (Picture 2)
Step 4: Generate the Image!
Open POV-Ray, then open your .pov file generated by Eagle3D. Click Run, and you should see the image being generated, with a live preview. This generated image is automatically saved in the same directory as the .pov file, and is also named the same. If you would like to change the camera angle, you can do so by regenerating the pov file with Eagle3D, and changing the Camera Settings tab. If you would like to change the image size, you do so in POV-Ray beneath the "New" icon.
Step 5: Other Ideas
Creating your own parts
Eagle3D only includes a number of parts, and you can expand your library. Here is a link to a tutorial showing you how to create your own parts.