I've spent the last 6 years mucking around in C++ (and 7 years prior to that in assembler and Delphi) trying to develop my skills and my attempt at a simple game, but I always found myself fighting with the engine that I was writing. Fighting in the sense that it didn't support the 4 billion features I wanted yet (seeing I had to write them), or my lack of knowledge of 3D math making life a little difficult for me. So I spent more time wrangling with the beast that is DirectInput, and then back to windows messages, and the strange and numerous macros that microsoft use to write windows apps, which I totally want to avoid. Then, about 3 years ago, along came the wife. And then the kids. The programming after hours eventually slowed to a halt. At the start of this year I decided to bite the bullet and try moving it all to C# instead, seeing I have about 6 years experience with professionally, writing mostly large scale n-tier database / ASP.NET applications (written entirely by myself) and I love the simplicity of it. So here I am, ZMan's words ringing in my ears about using prebuilt libraries instead of building my own, which I was doing mostly to learn from it, which was fine. But my life has changed. I'm part way through writing my own engine. I have network support via UDP (its not the best, but it works), a relatively simple GUI that I'm quite proud of, and a mostly working input library (mouse,keyboard,joystick). However, the gaming / graphics industry is moving forward at incredible speed, and when I started writing my engine way back in the previous millenium, cutting edge graphics was Doom 1. The prospect of writing a renderer with all the mod cons that engines like Irrlicht and Ogre support basically scares me. I don't see myself as having the skill to write such an engine, let alone in my lifetime! Now, while the subject of writing engines definitely interests me. So does writing an operating system, but I'm not going to write an OS. I started once, write 20 lines of assembler and gave it up as a silly fascination. So it comes down to the fact that... I'm over wanting to build my own! There are much smarter people out there writing much better engines than I ever could, faster than I ever could. So, to get to the point, what I really want is a C# game engine. My google searches have come up very thin on the ground. Axiom sounds good, but isn't in any state to be usuable (or obtainable by the look of it). I have Irrlicht.NET, and I have OgreDotNet (though I can't get it running yet), but they are graphics engines only. I could merge them with my own, and I still may, but if there is a free or even a relatively cheap C# game engine that I should know about, please let me know! Then there is the other option. Going back to C++ and using C4 or Torque. I see differing opinions on Torque, being mostly bad unless you get the shader engine add on, and while C4 is written by a respected author, it doesn't yet have a large community. So I'm stuck. I keep changing my mind at the moment because I don't know whether to stick it out with C# (I really, really want to), or move back to C++ (it's semantics get to me, I hate header files, I don't know much about STL, and knowing that .NET is the platform that microsoft is moving towards makes it harder still). I appreciate your views and opinions.

You should definately look at the open source Haddd Engine (look at the site for screens) now called JadEngine as it is definately the most advanced C# engine I have seen.

Hey, I'm in the same boat as you. I've been scouring for a really good C# engine but haven't came across anythign that great (for free that is). However, one that is really promising is Brume.

http://chrisk.free.fr/cariboost2/crbst_0.html

Its a great engine with physics and collision detection etc, however the one thing I don't like right now is that the terrain loading is sketchy. They are improving it I believe. Another drawback is the community doesn't seem to be that large, but for all intents and purposes its a decent engine.

Here is also a list of some current C# engines (both graphics and game)

http://www.devmaster.net/engines/list.php?fid=6&sid=2

Good luck, let me know if you find something solid, as myself am still looking.