In 2005, Californians paid out $35.9 billion and received back $31.2 billion. That's a gap of $4.7 billion. That's a lot.

Do you think the amount of money the state receives indirectly from tech companies run by Americans educated in out-of-state colleges exceeds this amount? The figures for this are much harder to come by, but I suspect that the state makes back at least a same-order-of-magnitude amount of what it pays out.

According to wikipedia, there were 386,000 tech workers in the Bay Area in '08. If we assume that half of them are Americans from out of state, then they'd have to pay about $5000 in taxes a year to make it worth it, assuming that there's also a multiplier of 4 due to workers in other industries being hired to serve them.

Of course, all this assumes we're running on a "we pay you taxes in exchange for your nerds" model, and it may be more complicated than that.