System 38
The IBM System 38 was a precursor to the AS/400 which was later called the iSeries. This was the brainchild of IBM engineer Frank Soltis.It was also a descendent of the fabled IBM 'FS' project, which was designed to be a followup/replacement for the System/360 and System/370.
So the System/38 was nearly the System/380, and the AS/400 was nearly the System/40 :-)