1675 – Gottfried Leibniz demonstrated integral calculus for the first time to find the area under the graph of good ol y=f(x). That is, if you believe what he wrote in his notebooks.
1930 – Albert Einstein, yes that Albert Einstein and Leo Szilard received a US patent for a refrigerator that required no electricity, just a heat source. Electrolux bought up the patents.
2006 – The Sony PS3 went on sale with a built-in Blu-ray player and hard drive.
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