For those looking for a little more excitement in their lives, here is a list of ways to get yourself in trouble with the IRS: IRS Announces “Dirty Dozen” Tax Scams for 2006. The IRS doesn't seem to have released the 2007 list yet. My favorite is the Frivolous Arguments section:
Promoters have been known to make the following outlandish claims: the Sixteenth Amendment concerning congressional power to lay and collect income taxes was never ratified; wages are not income; filing a return and paying taxes are merely voluntary; and being required to file Form 1040 violates the Fifth Amendment right against self-incrimination or the Fourth Amendment right to privacy.Claiming immunity to taxation under the 5th amendment? That's essentially claiming that illegal income is tax free. Sorry guys. It doesn't work that way.
Also interesting reading is Publication 525, Taxable and Nontaxable Income.