Virtual Minibrix

From LDraw.org Wiki

Virtual Minibrix allows you to experience all the joys of building in Minibrix – apart from the smell of the rubber – from the comfort and convenience of your computer. The software is very heavily based on the LDraw family of tools. Minibrix was an early forerunner to the modern interlocking-brick construction sets such as LEGO. It consisted of very realistically-coloured rubber bricks, and was made by the Premo Rubber company of Petersfield, Hampshire in England from 1935 to 1976.