AARP -- Solitaire and Mahjongg

3D Mahjongg

Dubbed "3D Mahjongg," players match any tile that has two adjacent sides free to score points, and online buddies are plenty. The goal is to match tiles as quickly as possible to complete all the levels before the time runs out.

Spider Solitaire

Based on the classic card game, Spider Solitaire is known as the king of all solitaire games. "One must be skilled at manipulating the cards they've been dealt with. Overcome challenges and bad cards. Treasure the good cards you have. Use them wisely!" said AARP.

Remove all cards from the 10 columns to win the game. Cards are removed if you can form a sequence from King down to Ace of the same suit in one column.

Players vs. Players

As an added bonus, many games allow you to challenge other players. Adjust the game to your skill level and see how you rate next to top players.

Do Brain Games Really Work?

The jury is still out. Differing studies include differing opinions.

Popular Science quotes a New Yorker piece about recent studies, and some are on the skeptical side.

A study comparing dual training program among avid self-improvers in Silicon Valley came with a placebo game and with not playing any games at all in healthy young adults. The researchers, from three different U.S. universities, found the games improved people's ability in the games but not in independent tests of fluid intelligence, crystallized intelligence, multitasking or other capabilities. 

But other experts beg to differ.