Very interesting, fun way to spend a few minutes
For those who complain about the difficulty, sitting as far as you can get in the upper left hand corner of the screen makes it impossible for any enemies except the IRS jets to hit you. Just shill there and dodge down to grab the pots of gold, safes and 1ups.
That aside, I think it takes a bit too long to accumulate the full $10kk for the amount of challenge in the game. Once you've found the safe spot or learned to deal with each of the foes, there's very little challenge, but a lot of money to collect.
It didn't make sense to me that the boss comes at $8kk not $10kk but that's no big deal.
big spender medal didn't work for me unless there's an upgrade I missed.