Shaun’s Big Lunch (shaunthesheep.com)
This game has been around for a while now, but I thought I'd write about it because I think is very good.
The core mechanic is very simple and effective: move the slice of pie in the central tray to one of the four plates (up, down, left or right). Because you can't rotate the slices, you need to ensure the correct "slot" in the plate is empty, or you lose a life. There's a time limit for each slice, so you need to choose quickly. Sometimes it's very easy, other times I could feel the wires in my head struggling to find the best empty slot.
In addition to the basic game mechanic players get extra points for completing a plate with matching food for a sheep. Sometimes a sheep is replaced by a pig. Pigs prefer "a mix of everything", so a matching plate would result in a low score.
In sum: 4 plates in 4 directions, 4 different pies with 4 slices each, and 2 types of animals. I think this game is not only addictive, but also very educational.
You can play the game online at shaunthesheep.com.