Simtel
Simtel (sometimes called Simtelnet, originally SIMTEL20) was an important long-running archive of freeware and shareware for various operating systems. The Simtel archive had significant ties to the history of several operating systems: it was in turn a major repository for CP/M, MS-DOS, Microsoft Windows and FreeBSD. The archive was hosted initially on the MIT-MC PDP-10 running the Incompatible Timesharing System, then TOPS-20, then FreeBSD servers, with archive distributor Walnut Creek CDROM helping fund FreeBSD development.