The
RM Nimbus family of computers was developed by the UK's leading
educational IT supplier,
Research Machines*. By the mid-1990's, these machines were simply badged PCs running
MS-DOS and
Windows 95 (and
DooM, in 99% of cases). Prior to that time however, RM Nimbuses were bizarre
proprietary machines, ostensibly
Intel 80286 (or earlier)-based PC hardware, but running completely whacked-out RM applications and network software.
MS-DOS formatted floppies wouldn't work on them. Most PC software wouldn't work on them, let alone recognise their bong-addled bastardisation of
EGA displays. Most schools had dozens of these machines connected by networks that appeared to be
10base2 ethernet, but ran at speeds only slightly in advance of loading from
cassette tape.
RM Nimbuses were often loaded up with software packages such as Caxton Press, Art and Time, and a paint package that I cannot remember the name of, but which featured a 'stipple' tool that was used to draw 16-colour Christmas trees by every English child born after 1980. I believe, although cannot verify this, that some RM Nimbuses were able to run BBC software. Needless to say, these computers were complete bollocks and the keyboards were usually filthy.
*see government-mandated monopoly