The Vilna Gaon

Ya'akov Bleiman, as the winner of the 1963 Israeli youth championship (detail from Tarbut Encyclopedia, from Mrs. Sarah Bleiman's collection.) 

Chess prodigies are not often known for achievements outside chess, although certain exceptions exist -- the most famous being probably Philidor, who was also a talented musician, and Emmanuel Lasker, a mathematician and philosopher.

I suggest that perhaps the man who made the greatest contribution to society outside chess was Ya'akov Bleiman (1947-2004). A child prodigy from Vilnius (Lithuania), he came with his parents to Israel in the 1950s and quickly began to win numerous tournaments in the 50s and 60s. Nicknamed the "Vilna Gaon" (the "Genius from Vilnius", after the title of the famous 18th century rabbi), he received a rare tribute: a picture of him (painted from a photograph) was published in what was then Israel's most popular general encyclopedia for youngsters, Tarbut (see above). There is another picture on the same page -- of Emmanuel Lasker... 

He then studied engineering, and was the head of the Israeli SPICE project. He won both Rafael's "manager of the year" award and the Israel Defense Prize -- Israel's top award for defense-related projects -- for heading the project. He sadly died of ALS ("Lou Gehrig's disease") when only 57.