Yup, the Palo Alto Research Center was responsible for so, so much of current user interface technology, yet they couldn't capitalize on it.

In a similar vein, AT&T's Bell Labs developed the solid state transistor, couldn't figure out what to do with it (they were thinking hearing aids), gave it away for next to nothing to Sony, which spurred Japan's entire economy into the upper echelon for decades.

More a marketing disaster than a technological one, I was a user of Osborne computers in the early 80's. Adam Osborne announced the Osborne Executive, with great advances over the current Osborne 1, well before it was ready for market. Sales of the Osborne 1 (their only current product) dropped to near nothing all as everyone waited for the new product (which wasn't nearly ready when it was first announced). The Osborne Computer Corporation went bankrupt within a few months of the disastrous announcement. A shame, as I had both an Osborne 1 and an Osborne Executive, and liked them very much.