The Merlin Tonto computer was sold by British Telecom and was a re-badged version of the ICL One Per Desk Computer.

Both computers were released in late 1984 / early 1985 and based on the Sinclair QL Home Computer, and included improved ZX Microdrive units and a built in telephone and modem, phone directory, speech synthesizer and Psion Xchange on EPROM.  It was also released under the name Merlin Tonto for BT and the Computerphone for Telecom Australia (APT).  There were even a few machines released for North America.

The links between the these computers and the Sinclair QL relate mainly to the hardware, with the same 68008 CPU, the two main QL ULAs (the ZX8301 and ZX8302) and the built-in microdrives - the same method of RAM and screen management was also implemented, although most QL software will not run on the machine.  As with the QL, the One Per Desk included 128K of memory (with 32K being used for the screen), but also included an extra 2K of battery backed CMOS RAM.  It appears that the maximum memory that could be added was a further 128K (giving total 256K RAM), compared to the Sinclair QL - however, as it was planned for the majority of software to be provided on ROM (for immediate loading), this is not too much of a problem.

With everything built into the one unit, these proved popular with some call centres, although the additional hardware and even software is now quite rare.