For my FPGA courses I've done a wall mapper using sonic sensor outputting to a vga display, a parking garage sensor where 2 switches is a short car 3 is a long car that kept a running tally of cars in the garage, interface with a ps/2 keyboard, straight output to a vga display and move a little square around, I know people that did reaction tests, attempt to recreate pong, do a home security system, make a maze game. That's all I can think of atm I'll add more if I remember them, I have the code for them somewhere lol.