dotNet Protector

PV Logiciels dotNet Protector is a powerful .NET code protection system that prevents your assemblies from being decompiled.
dotNet Protector 5 protects applications and components with a new body obfuscation technology.

Assemblies are no more merged in a win32 executable, but keep their .net nature. dotNet Protector 5 protects your code with a names obfuscator combined with a body obfuscator.
dotNet Protector 5 native runtime is available on X32, X64 and IA64 platforms
dotNet Protector 5 Engine is available for x32 and x64 architectures.