You might not have heard of Cacoma Knight in Bizyland, but it's kind of like Qix, only with better graphics and more plot.
It also gets pretty tough as you go along, so I like to go to the Mode Selection screen
and put in Not Quite The Konami Code
Up, Up, Down, Down, Right, Left, Right, Left, B, A
Which takes me to the "Special Presents" menu
Where I get to play with all kinds of settings, including how many lives and continues I get, as well as my starting round.
Which is great when I get frustrated and stuck so that I can see the rest of the game.