a) There might already be something like that. A local guy sold Great Plains to MS years ago for over a billion dollars, and has done a lot to renovate the downtown area and has a local venture fund.
This discussion is shaping up in the other thread: https://news.ycombinator.com/item?id=5578195 . Also, I've been discussing it with other people for the past 48 hours. Austin is getting a lot of recommendation. I feel like #4-10 tech hubs are probably better targets than nonentities, but we'll see.
As I think about it, I don't want the governments footing the bill. I'd prefer to have at least 50% private investment (1:! matching?) as long as it's willing to stay passive enough not to interfere with engineer autonomy. Furthermore, over the long term, I'd want the ability of engineers to buy into the fund.
b) impossible