 Sinclair followed up the MK14 by producing the ZX80 , at the time the world 's smallest and cheapest computer , which was launched in January 1980 costing £ 99 @.@ 95 ( equivalent to £ 319 at 2009 prices . ) The company conducted no market research whatsoever prior to the launch of the ZX80 ; according to Clive Sinclair , he " simply had a hunch " that the general public was sufficiently interested to make such a project feasible and went ahead with ordering 100 @,@ 000 sets of parts so that he could launch at high volume . 
