If Amazon's top-sellers list is any indication, Americans are fed up with rising income inequality.

As of Thursday evening, Sen. Elizabeth Warren's new memoir, A Fighting Chance, is the number two best-selling book on Amazon, trailing only Thomas Piketty'sCapital In The Twenty-First Century. Michael Lewis' Flash Boys, which exposes the world of high-frequency traders, is number five. Both Capital and A Fighting Chance are also among Barnes & Noble's top five sellers. Rounding out Amazon's top five are John Green's YA hit The Fault In Our Stars and an illustrated Little Golden Book adaptation of Disney's "Frozen." Both books are more representative of typical Amazon best-sellers, which tend to include popular fiction and self-help titles.

While the three works come at the issue from different vantage points, they all arrive at essentially the same conclusion: the game is rigged against the middle class.

Warren's book, released Tuesday, traces the Massachusetts Democrat's journey from law professor to U.S. senator. The book details how the struggles Warren's middle class parents faced motivated her to work toward remedying income inequality -- most notably, in her role in the creation of the Consumer Financial Protection Bureau.

“This book is about how Washington is rigged to work for those who can hire armies of lobbyists and lawyers and make sure that everything that they want gets done in Washington,” Warren told ABC News earlier this week. “The game is rigged to work for those who already have money and power. I wrote this book because the way I see it, working families, they're not looking for a handout. They're not looking for some special deal. They just want a level playing field. They just want a fighting chance."

Meanwhile, Piketty's manifesto has become an unlikely hit. The nearly 700-page tome is currently sold out on Amazon, as Harvard University Press scrambles to print an additional 80,000 copies. In the interim, the French economist has been on a dizzying U.S. tour, meeting with the likes of Treasury Secretary Jack Lew, the Council of Economic Advisers and the IMF, in addition to giving dozens of interviews to major media outlets.

Based on analysis of over 200 years' worth of economic data from 20 countries, Capital argues that unfettered capitalism will inevitably lead to extreme income inequality. If world leaders are unwilling to shrink the widening gap by, say, imposing a global wealth tax or other mechanisms, the rich will continue to grow richer, leaving the rest of society behind. As Piketty explained on HuffPost Live last week, this could cause capitalistic societies to revert back to the economic conditions of the 18th and 19th centuries.

Flash Boys, Lewis' New York Times bestseller, sheds light on the predatory practices of high-frequency traders. According to Lewis, these traders are essentially able to front-run typical investors by using lightning-fast network connections to quickly buy stocks and sell them back. Lewis' work was featured in a popular "60 Minutes" segment last month.

"It's bigger than a scam," Lewis said during the segment. "It's the stock market."