IBM Convertible
The IBM Convertible was the follow-on to the IBM Portable, and was IBM's first attempt at a laptop computer. The Convertible was as powerful as the Portable, but could run on batteries and was marginally more practical. However, it had a number of design flaws that stemmed its popularity. It was released in April of 1986, just over a year before the release of the PS/2 series (with which it shares many of its styling cues).The Convertible had two 3.5", 720 kilobyte floppy disk drives (the first IBM PC to come with 3.5" drives as standard equipment), and could accept a number of attachments and gadgets (including a thermal printer and special monitors that attached to the LCD port). It was also one of the first machines to support standby mode. However, the Convertible was heavy, not much faster than the Portable it replaced (despite the newer CMOS processor and use of static RAM), didn't come with traditional PC expansion ports (such as serial ports and a parallel port) without an add-on, and had a hard-to-read, oddly-shaped LCD screen (the first screens lacked a backlight).
Because of these flaws, the Convertible was largely ignored in favor of products from Toshiba and Zenith. IBM would not release another laptop until the advent of the ThinkPad.
Picture of the IBM convertible 5140:
