Auction Off Immigration Spaces

The Senate immigration bill looks like it probably won't pass. As the WSJ$ reports even businesses don't like it:

"Even constituencies that appear to benefit from the Senate legislation, such as high-tech businesses, were skeptical. In a letter to Senate Majority Leader Harry Reid (D., Nev.), Microsoft Corp. said the plan to distribute visas using a points system 'would take hiring decisions out of the hands of employers and could potentially harm the technology industry."'

What I would like to happen is for the U.S. to auction off immigration slots. If the government, say, wanted to let in 400,000 people next year it would give the slots to those willing to pay the most. The government would only check to see that a potential immigrant wasn't a criminal or terrorist. This way companies could quickly get valuable workers. Also, people willing to pay the most would probably, on average, be those who would contribute the most to our economy.