ASPack

A very competent Win32 compressor by Russian author Alexey Solodovnikov.
After compression of the executable image, ASPack writes a small decompressor and places icons at the end of the compressed file.
The address of the application's entry point is set to the beginning of the decompressor, and the original entry point is saved.
After the decompressor decompresses the image in memory, it jumps to the application's original entry point.
ASPack makes Windows programs and libraries smaller, it also protects programs against reverse engineering by non-professional hackers.
Programs compressed with ASPack are self-contained and run exactly as before, with no runtime performance penalties.