PEiD (short for PE iDentifier) is a well-known professional packer/cryptor/compiler detecting tool. It's so powerful that it can detect the types/signatures of almost any PE file packing tools (at present, the number has been more than 600 kinds). In addition to the official version, AppNee also provides you its full-plugin version, which can be treated as the most perfect one version (contains 60+ plugins and necessary runtime library files: mfc70.dll, msvcr70.dll, rtl70.bpl, vcl70.bpl) on the Internet at present. I do believe reverse engineers or software cracking/unpacking enthusiasts must like it very much.
Exeinfo PE is a popular and universal free analyzer & detector to executable files' packer/compressor/compiler, written in Delphi by A.S.L from Poland. It is capable of detecting 300+ binary data types (non EXE formats and more signatures on Ext_detector.dll) with info about how to open them via some free tool.
As one of the most important and effective OS maintaining tools, Windows PE had become necessary for a long time. And in many cases, it is the key to solve troublesome system boot failures. While as a matter of fact, it is hard to find a high-quality WinPE image file on the Internet (so as to burn it into a USB/DVD media for use). As a consequence, a lot of advanced computer users chose to build their own PEs.