My AP Government classes have been studying the Amendments to the Constitution and just yesterday we were talking about the 27th Amendment which prevents Congress from passing and receiving a pay increase without an intervening election.
No law, varying the compensation for the services of the Senators and Representatives, shall take effect, until an election of Representatives shall have intervened.
However, the canny politicians in Congress have found a way around this. They characterize their "pay increases" as "cost of living increases." And then they made those increases automatic. They go into effect without a vote unless someone introduces an amendment forcing debate and a vote. And, if you look at the history of Congressional pay raises, it's clear that, except for a brief period in the 1990s, they have all agreed to not stop their automatic pay increases from taking effect. You can check out this chart which goes through 2002, but they managed to get their raises again in 2003 and 2004. Aren't our elected officials clever in how they can get around the Constitution when their own self-interest is involved?
By the way, the 27th Amendment is an Amendment with a marvelous history. It was originally proposed by James Madison along with the ten that became the Bill of Rights. However, it wasn't ratified by the required 3/4 of the states and so didn't enter the Constitution. However, in the 1980s, a college student discovered this history and began an effort to get that requisite ratification from 38 states, and in 1992, the 27th Amendment was added to the Constitution. As I tell my students, what could be cooler than doing a research paper for college and ending up spearheading a movement and successfully amending the Constitution? Too bad that the Congressmen found a way around Madison's amendment.