One of my favorite exercises is explaining real income and improving per capita gdp. The Federal Reserve Bank of Dallas had some great tables in their annual reports in the 1990s. They showed how the real cost of many common items fell as a result of improving productivity and how standard of living related to labor costs.
Now, there's another resource you can use. Check out this post by David Henderson on EconLib. It links to Radio Shack catalogs from 1939 to 2005. It's a little more up-to-date. And while it is limited to electronic gadgets, it still makes the point.
I'd be interested in your thoughts.