[orangecat]

DARPA's budget is about $3B this year alone.

Compared to $10 billion in R&D for Microsoft and Intel and $8 billion for Google: http://fortune.com/2014/11/17/top-10-research-development/

[mikeash]

Pretty much all of that money comes from selling stuff they are only able to sell because of previous government R&D.

For example, without the government leaning heavily on integrated circuits in the 60s, would Microsoft and Google even exist today?

[abalone]

...in late stage development which is MUCH less risky. Super risky early stage tech development mostly happens in the public sector at taxpayer expense through government agencies like DARPA.

[zo1]

A lot of things are easier when it happens with other people's money. A lot of those projects didn't necessarily have the expectation to make/turn a profit.