Macintosh IIsi (1990)
The Macintosh IIsi is a compact three-box desktop unit, effectively a cut-down Macintosh IIci in a smaller case (used for no other Macintosh model), made cheaper by the redesign of the motherboard and the deletion of all but one of the expansion card slots (a single Processor Direct Slot). It was introduced as a low-cost alternative to the professional desktop models for home use, but offered more features and performance than the LC series. It had color and could drive a number of different external monitors, with a maximum screen resolution of 640×480 in eight-bit color. It shipped with either a 40-MB or 80-MB internal hard disk, and a 1.44-MB floppy disk drive. The MC 68882 FPU was an optional extra, mounted on a special plug-in card. Ports included SCSI, two serial ports, an ADB port, a floppy drive port, and 3.5mm stereo headphone sound output and microphone sound input sockets. The IIsi was the first Macintosh released with built-in sound-in capabilities. The Macintosh LC, which was announced at the same time and also had a sound-in port, was released a number of months after the IIsi.
via Wikipedia: http://en.wikipedia.org/wiki/Macintosh_IIsi