There have been several engines propossed:
Both 1 and 2 are open source, while 3 requires that you own Unreal.
If there are no more suggestions, I will post a poll.
Definitly Unreal Engine…
Good Old Quake 3 Engine is still decent… I like it because the quality of the graphics is relatively high on low end systems. Medal Of Honor: Allied Assault was done with that engine and its graphics are very similar to spearhead and breakthrough while both of those games had stiffer graphic requirements.
The real reason i like it is because My Umax J700 Mac Clone with a G4 400 doesn’t run much of anything anymore (but I did get MacOSX on it…). Granted i will be getting a G5 around christmas, so the real question is, Will it be made for Mac OSX also?
Depending on what and how much i learn in My summer programming course this year i would be willing to help the OSX version.
Oh Yes and we most definatly need to be using OpenGL, NOT that Direct X crap.
Crystal Space. Just have to say it before the poll. The demo is awesome… 
I’m not involved with this game but … why is DirectX crap? I use it for all of my 3d games and it works just fine. OOP rules!
Because DirectX is a MS thing. OpenGL is platform independent.
DirectX is cool, though, because it is actually several things, input, 3D accel, audio/video, network, and a couple of others. Basically, you can do everything multimedia w/DirectX.
However, we will NOT be using DirectX or OpenGL directly, the engine will handle that.
And no, currently I am seeing Win32. (Ports may come in the future)
[And might I remind you that using an engine like Unreal or Quake means every developer will have to OWN it. If we use an open source engine like #1 and 2, we won’t have to spend $$$. Unless we can get the company to send us the engine now.]
yeah… i think i will put my vote up for Crystal Space, it can do OpenGL if you want it to, and it supports Windows, MacOS/X, Unix, Linux and others. Its also Open Source, i like that.
Well i hope that my my summer programming class helps me, i can program the robot controller with ease, but as you probably know thats not very real world, i currently know almost nothing, i know basic syntax because the programming cource durring school that i took last year was mostly Visual Basic with a little C tacked on at the end (CML interface too, no objects or anything like that, just enter a number and it will do what ever then display it, then exit)
I recomend Sams Teach Yourself Visual C++ 6 in 21 Days (ISBN 0-672-31240-9) for anyone who wants to.
The Torque engine (http://www.garagegames.com/pg/product/view.php?id=1) can be bought, source, updates, and the right to do what you want with (compiled) games developed with it, for $100.
Problem: It’s for $100 , certainly it is a nice package, but for $100 , I still prefer a free engine.
But, If I had to buy something to get an engine, I’d get Unreal Tournament. Not only do I get an engine, but I also get a great game. All for probably half the price.
I just did an initial pass of Unreal (http://www.unrealtechnology.com/html/homefold/home.shtml). I think it would be cool, but check out licensing (http://www.unrealtechnology.com/html/licensing/terms.shtml). The e-mail (for anyone brave enough) is licensing@epicgames.com.
I think we won’t be able to go open source, to say the least.
If a one time $100 fee scares the developers, they have a huge misconception of this project. It will take many hundreds of man-hours to get to version 0.1, enough time to make far more money than $100.