They probably won't put you in jail, but they can seize your bank accounts, garnish your wages, and do other horrible things to your body.
Go ahead, mess with them. It might take them a few years to catch up, but that's OK, if you never file, then the statute of limitations never starts to run, and they will go back to the dawn of time and assess taxes, interest, and penalties . . .
I am a tax accountant, so this is very old, boring news to me. Suffice to say the 16th Amendment WAS ratified, and 26 USC gives plenty o' authority to tax you.
But don't take my word for it. Be a real man and stop filing (be sure to cut off your withholding too, otherwise you are a big puss). Better yet, file a return showing no income and with the perjury statement crossed out, claiming that you are not a citizen of the US, just the state in which you reside, which does not make you subject to federal income tax. Make sure to include a map to your house
Then, after they assess you, you have three choices:
1) Pay what you owe
2) Contest the assessment in US Tax Court (you will lose, and be fined $5K+ for making frivolous arguments)
3) Pay what you owe, and sue for a refund in US District Court (you will lose)
Either can be appealed to US Court of Appeals (you will lose), which can be appealed to the US Supreme Court (you will not be granted certiorari).
You might find tax protesters pointing to a recent case where a famous dude was not found criminally liable because they believed tax protester arguments. The tax protesters will claim that's proof nobody has to pay. No, that just means you MIGHT not go to prison. They still had to pay . . .
Any other questions?