From Just Solve the File Format Problem
IMP is a full-featured compression and archive format, and associated (now unmaintained) software, developed by Technelysium Pty Ltd.
IMP files begin with signature bytes
'I' 'M' 'P' 0x0a.
- IMP 1.1 - DOS
- IMP 1.12 - Win95/NT (Windows console, untested)
- WinImp 1.2 (Windows GUI, untested)
- IMP archive extraction source code v1.13