The ultimate home and business computer from Sinclair. The QL was expensive and powerful. Unfortunately it never took off. The machine stored data using quirky microdrive cartridges that were rather fragile. The QL was far more useful with a 3.5" diskette drive. My machine has such a drive with interface. Here's an interesting article about the QL. The QL had advanced features like networking, pre-emptive multitasking OS and a 32bit CPU. Released in 1984 the QL was ahead of its' time. The QL used a Motorola MC68008 CPU running at 7.5MHz.
Inside the Sinclair QL. Notice the two microdrive units on the right.