The one that's going to bitch slap the middle class is all those IRS agents. I can see them targeting contractors and independent small businesses that deal largely in cash sales. Contractors use lots of subs and often pay workers on a 1099. Many keep pretty iffy books. That's the sort of thing the IRS will target for back taxes. Then they'll slap a lien on the business to squeeze them endlessly for back taxes and interest. Miss a payment and they take the business.
It will cause many of these people to simply fold up shop or go underground (eg., black market) rather than deal with the IRS.