Feasible to sue ignifuge.com?

As many of you may recall, during the height of the internet banner, make money phase, there were many companies that paid you to have their banner on your desktop. Some companies paid you for your visits to their homepage. The idea was that the advertising revenues would be shared with the members (you) and thus anyone can surf the web and make money in the process. Those who referred a lot of people made a lot of money.
Well almost all of those companies have since died out but one is still up and active and owes me at least $70. www.ignifuge.com sells itself to members that they will pay for you sent ignifuge.com as your homepage. For each visit by you and your referrals you would be paid accordingly. Each month, checks are sent out to members who accumulated more than $20. I have had a $70+ balance sitting in my account (still active, I can log in, but have long lost faith in the program). I never received a check. They do not answer their customer support e-mails. The money was due at least 3 years ago. How can they still be in business? Granted those companies were always shady and questionable and here today and gone tomorrow, but this company still exists, still sells itself to recreuit members, and stillmakes revenue from advertisers and sponsors. I have threatened to sue and/or report them to the proper authorities, yet they never responded.
I am fed up with them. It is more principle than the money. Is there anyway I could get them in a lot of trouble and/or sue them for what is owed to me? Are such actions feasible? Does the FBI fraud department even care?