From PELock Software:
.netshrink is an executable compressor and DLL binder for .NET applications. It uses LZMA compression library and can decrease your file size even by 50%. With .netshrink you can also bind multiple DLL libraries to the output file so you can redistribute your application as a standalone file. It can also protect your files with a password. Password protection uses verification based on SHA256 hash function and 256 bit AES / Rijndael encryption.