RAR File Format

[Suicide Junkie]

Ok, thats lots more detail that I was hoping for

I don't use my ISP for most of those either.
However, having to go through their connection means that you still get hit with the common pricing and limits they have, if I understand what you're saying.

[Aiken]

I think, RAR is the best proprietary archive format in the windows world (best compression ratio/speed). 7zip has comparable characteristics, but it takes ages to pack large volumes into 7zip archive.

As for interface ... Rar integrates into Total Commander easily, so I always use rar archives as compressed folders. I even don't remember what WinRAR's UI is look like.