UHarc is a solid, high-compression 386+ DOS and Windows file archiver with multimedia support. It is written by Uwe Herklotz and is available in binary form, free only for non-commercial use.

Memory requirements depend on the compression method used (e.g., -mz needs less than -mx). Comparisons between WinRAR and UHarc generally show smaller filesizes with UHarc but a relatively substantial increase in decompression time (but much faster than PAQAR4, etc).

The latest beta is 0.6b (01 Oct 2005), but since 0.6a it has completely replaced the 0.4 and older archive headers and is not backwards compatible. There is a known limitation that archives must be smaller than a total of two gigabytes unpacked size, although there are some reports that it is possible to compress a 6gb unpacked sized archive.
link to GUI:
http://www.softpedia.com/get/Compression-tools/UHARC-GUI-by-Brhack.shtml