WinRAR
.sit
.tar
But I think my download is just broken, because I installed 7-zip in my virtual maschine and it said it can't recognise it.
7-zip is not really a good format. Even at my workplace, we always get problems with 7-zip files sent to us by customers, even if we install the program.
I'll redownload, maybe it's really broken.
WinRAR is IMHO the best way to go. It can be uncompressed on virtually every OS.