Black Out! is a clone of the classic puzzle game Lights Out (Wiki) which consists of a 5×5 grid of “lights”, some of which are on, and others are off. Flipping a particular switch will also toggle all adjacent switches (no diagonals, though). I wrote this game back in 2007, a few months after Breakout Pong.
Here’s a screenshot:
In the game, black squares are off, while yellow squares (representing lights) are on. Counters track the number of lights remaining and number of moves thus far. The game uses application settings to store an array of high scores. Reset will undo all changes and initialize the counters.
Like Breakout Pong, this was entirely in WinForms, using pictureboxes and a few other controls. The grid is procedurally generated, and most of the heavy lifting is done in a single OnClick handler, which was called when any of the pictureboxes received a click event.
I remember showing this to my freshman year roommate in 2008. It was fun seeing him play it, since I had long ago memorized the methodology and last row cases (see the Wikipedia article link to Lights Out for more info on that) and the game was no longer challenging. Unfortunately, the code for this game has also been lost (just like Breakout Pong), but the executable has somehow persisted in my system backups all these years.