Did this project in class the other day and wanted to put it up here. I had already done all the truth tables and karnaugh maps so putting it on here wasn't too hard (minus the fact that I got halfway through once and my program died and took my project with it).
The top switches are all off right now. Put in the binary number on the switches and the leds will display the decimal value. (0 through 9 of course)
Made it a hair more readable.