It doesn't matter if it was something you popped in just for a second to see if it worked, or if it was a game that you spent the last 36 consecutive hours with.
Just tell me. What was the last video game you played?
And now that I think about it, this is an embarrassing time to have posted the question. The last game I played was Sewer Shark for Sega CD (while testing out the emulator). GASP.