I have some neural net code written in c# that would benefit from using SIMD support. Mono 2.2 just came out that supports SIMD but Microsoft\'s c# does not support this yet
Essentially, if you write it with Simd and distribute the dll with your code, it will use acceleration if the target VM supports it. If not, it doesn't break. So you can use the library and give any users of your program who run .NET apps with Mono a speed boost.
Microsoft has been said to be planning to add such support in its next release of its runtime, though I cannot find the link and don't have it handy right this sec---can dig the link out of a historic backup if anyone is interested enough.