You really want to do something, start answering those calls and take down useful information. Help the FTC/FCC and local law enforcement by doing some of the investigation yourself. It is a fact that they advise against answering the phone, but at the same time they also ask us to provide them with any information we may have to aid their investigations. If you follow the tips below, you will be safe. Here's how to fight back:

1. Cost them money. By connecting a call, your costing them money as they get charged for every connection that is made.

2. Cost them time. There are so many hours in a given day and boiler rooms usually work 9-5 like a legit business would.

3. Do not get rude or ugly with them, but rather fain interest. Keep in mind that they do not care that you're on the NDNCL, or that you know the law, they are not offended by cuss words or sympathetic to tears...all they care about is money. (Not to mention the fact that if you make them angry, they already have your number and can make it a point to call you as many times as they like.) So act like the mark that they think you are and play the victim, after a while ask for a call back number...the number they called you from is almost always spoofed, but if they want your money the number they give you to call back will be working number. That number can usually be traced to an owner/company name and physical location. Also ask for a website.
If you have VoIP or a spoofing app, verify the call back number...if not post it and somebody else will.

4. If you have a call blocker, you can now block their number because you have learned their information, and if they have provided you with a call back number, you can block that one as well, so you have two numbers you can block instead of just one.

5. Post all the information and numbers you get here so that not only you, but all the other people interested can have the information available. They can use that info to seek justice.
Example: " Had a call from xxxxxxxx, and spoke to a person who said they were selling xxxxxx. I asked the name of their company and they told me xxxx, and the website they gave me was xxxxxxxx .com they also gave me this call back number xxxxxxxxx" Post the out going number and the call back number separately so you're sure each has its own listing.

6. File a complaint with the FTC.

7. Sit back and eat popcorn knowing that others are using the info you've provided helping them to seek justice and who knows, you may read about an arrest made or see it in the news.