Proton is the retro-futuristic, self-contained, abstract strategy PocketBoardGame for 1 or 2 players. Take turns moving the sliding tiles to connect the endpoints with a path of your color.
You might decide to simply move the endpoints closer together - but then they'll be closer for your opponent as well, so watch out! Or try a solitaire challenge: can you connect the endpoints with both colors simultaneously? What's the longest path you can make? Can you make a symmetrical path?
This is a great game for playing while waiting in line, or any other place where there's no room to lay out gaming equipment. And it fits in your pocket, so you can take it anywhere!