Aah the PET.. dad borrowed one from work circa 1980 and bought a 'housefinder' program at great expense. Relied on one inputting all houses on the market from the local paper and offering a search function to narrow the list down for potential buyers. Never did catch on. I think I've still got the cassette... whats that worth then?
Speccy.. fond memories. Bought the 16k version then found that most software (including Flight Simulator) needed 48k.. bought the chips on mail order, hey presto, the thing did years of sterling service till I sold it at a car boot sale a few years ago for a tenner, including all the software I had collected.
BBC Micro.. niche market IMHO