Freecell - which comes free with Windows - lets you play a fun solitaire card game on your system. A nice way to pass some time and sharpen your brain!
You have a variety of options for the appearance - different card deck styles, different backgrounds. I love the 'seasons' deck with bird nests and flowers, put on the green leafy background. There's even a large-size deck if you have vision problems. You can drag and shrink the entire board and the cards will auto size to fit the space available.
You have eight columns of cards to work with. Your aim is to end up with four stacks of cards, each with an ace at the bottom and the king at the top, of each suit. To do your work, you have four other holding areas. You can put any cards you wish in this other area. It is solely for putting away cards temporarily, while you work with the cards in your main area.
You can see all cards on the board, so nothing is ever hidden. This is a pure strategy game. How do you arrange the cards across your columns? You can move cards from one column to another as long as the card you're moving is one number below the card you're placing it on, and is of the opposite color. So if a column currently ends with a red 5, you can move a black 4 onto it from any other column. Your aim is to move the cards around, slowly, carefully, to free up the aces. The aces can then move into the "final spot" area. Then you seek out the 2s, then the 3s, and so on.
You don't want to move cards too quickly. Even if you CAN move a 3 into the final pile, you don't necessarily want to do that if the 3 can be useful in freeing other cards in the active area.
This is not a fast-clicking game. It's not about killing the aliens before they kill you. Rather, it is a brain sharpening game. It's about seeing patterns in numbers, about thinking ahead and planning out your options. If you randomly put cards in spots you're unlikely to reach the goal of clearing the board.
Highly recommended as a way to pass time which is both fun and mind-sharpening!