I applaud your sentiment, but honestly, if you can afford Internet access, you can afford a one-time $1 (or even $5) sign-up fee.

I'm sure people will come up with some scenario where that's not 100% true, but I think it generally is. And you could probably devise alternate solutions for those exceptions. Some ideas off the top of my head:

1) The sign-up fee could be waived for anybody signing up with a .edu address.

2) Integrate with major library systems, and say the sign-up fee can be waived if you authenticate with a local library, enter your library card number, etc.

3) Offer a refund of the sign-up fee after 6 months of non-troll behavior.

I don't know. But I do think the benefits of having some money on the line and some basic identity verification outweigh the risk of drowning out some voices.

Alright, let's say 10¢. Everyone with a personal Internet-enabled device can most certainly afford that. You could even refund them the money later, as the goal is to obtain the payment identity -- not the cash.

Not everyone has a way to pay online, especially if you are accepting credit cards.

You can add funds to a PayPal account without a credit card. You can buy a PayPal card with cash or send funds through MoneyGram. There may be a minimum required amount though. I'm not entirely sure of the specifics, but I know, in general, it's possible.