Similarly, some argue that because we have a “voluntary” system, taxes are optional. But voluntary only “means the government is trusting you to self-report how much tax you owe,” instead of the government telling you what you owe, says George Willis, an associate clinical professor at Chapman University School of Law.
Bartering is tax-free: Bartering has blossomed in the recession, particularly online. But while no money changes hands, the value of the swaps is taxable income for both sides, Quijano says.
Internet revenue isn’t taxable: Online entrepreneurs who believe this are in for a rude shock next year, says Barbara Weltman, author of J.K. Lasser’s 1001 Deductions & Tax Breaks. That’s when credit card companies and groups like PayPal must start reporting merchant sales to the IRS, she says.
Ill-gotten gains aren’t taxable: Even if your line of work is theft, embezzlement, prostitution, drug dealing or some other illegal enterprise, that income is still taxable.

See the full article from “American Chronicle”