If you've got 20 minutes to spare and you want to play a relaxing game of mahjong, check out Master Quan's Mahjongg. While it doesn't do anything groundbreaking that other mahjong games don't do, it is a simple way to relax when you need a break from your regular day.
If you've played other computer mahjong games, you know what the drill here. You have a layout of beautifully decorated mahjong tiles, and your goal is to find matches for each one. You can match identical tiles with each other, but you can also match flower tiles with other flowers and season tiles with different seasons. You also have a 20-minute time limit to complete as many mahjong puzzles as you can. That sounds like it might be a lot of time, but anyone who has played mahjong knows that you can stare at the screen for minutes at a time and not see what should be an obvious match.
Time limit or not, Master Qwan's Mahjongg is still a great mahjong game. The graphics are pleasant, it's set to relaxing music, and trying to beat your previous score is addictive. Give it a try the next time you have a break.