Not a lot of people know about this, but back in 2001 Discreet (before the company was purchased by Autodesk) released a free version of 3ds max for modding games. Back then game file formats and tools were much more highly specialized than today, so each game required a "game pack" to customize the gmax interface to support that game. I think the idea was to charge the game developer money to add support for their game. Gmax supported several titles including Quake 3 Arena and Microsoft Flight Simulator, but was later discontinued.
I personally love the program because it includes only the features you need from 3ds max for hard surface modeling. It's basically a stripped down version of 3ds max with only the features you need.
Gmax still survives today, apparently in the custody of Turbosquid. You can download it here. You need the gmax 1.2 installer and the Tempest game pack for Quake 3. You will also need to request a free registration key from Turbosquid. After installing gmax, you can simply find the MD3 export plugin ("md3exp.dle") in the Tempest game pack download and copy that to your "C:\gmax\plugins" directory to enable export. There is also an optional There is also an optional MD3 import script by Chris Cookson which is uploaded here for safekeeping:
With the plugin system in our new engine I was able to add support for loading Quake 3 MD3 models, so you can export your gmax models and load them up in the new engine. However, there are some restrictions. The MD3 file format uses compressed vertex positions, so your vertex positions have a limited range and resolution. Additionally, there are restrictions on what you can do with the gmax program, so take a look at the licensing terms before you do anything. Still, it's a fun program to have and this is a nice feature to play around with.