I stumbled across some interesting pictures on Flickr today. It’s Rick Dickinson, who was a designer for Sinclair Research. Here are some sets, including sketch ideas for the ZX81, as well as products which never made it, but were under development at Sinclair.

http://www.flickr.com/photos/9574086@N0 ... 812198325/

For example, how the ZX81 RAM Pack SHOULD have fitted to the machine:

zx81 ram by Rick Dickinson, on Flickr

Or this computer case design which reminds me, and clearly others, of the PS2:

waferStackModel by Rick Dickinson, on Flickr

See if you can find the Apple Puck Mouse look-a-like!

For years I've wondered who did the great cover artwork for the ZX81 Manual and now I know.

Very interesting collection of images.