SDF Public Access Unix System
This may be the appropriate place to gratefully mention Polarhome (http://www.polarhome.com/), that for many years managed a "dinosaur zoo" of ageing Unix systems, on which one could buy a login for a nominal fee. Very convenient for me as developer of a portable Unix utility (rlwrap) - it allowed me to spot many portability problems (often real bugs that manifested themselves only on certain systems).Sadly, Polarhome has thrown in the towel. Does anyone know of something comparable, i.e. not only a public access Unix system, but one that offers a range of Unices?