Machinarium is a cross platform indie point and click adventure game that costs $9.99.
Pro Interesting protagonist
The main character and the one controlled by the player is just a normal, average, everyday robot. He doesn't have any special powers or abilities other than being able to slightly extend his midriff in order to reach high ledges or making his body shorter. He's pretty much an ordinary robot thrust into an extraordinary situation.
Pro The well-designed gameplay mechanics avoid making the game boring to the player
Unlike most point-and-click games, objects of interest in Machinarium light up only when the main character is close to them; this completely changes the way the game is played. In point-and-click games where this is not the case, the gameplay is usually reduced to aimlessly flailing the cursor around waiting for something to light up.
Machinarium on the other hand completely avoids this, keeping levels interesting and the player interested to the game.
Pro Built-in hint system
For those that do find some of the puzzles too challenging there is an inbuilt hint system shown through "thought bubbles" on top of the playable character.
Every level has its own hint when pressed and it's usually a hint on where to go or what kind of object you need. Although it's advised not to rely on the hint system too much since it takes away from the experience of actually enjoying the game.
Pro The gameplay is perfectly interwoven with the overall aesthetic and atmosphere of the game
The player is forced to move their character across the map in order to find objects of interest. This, coupled with the great sound design and soundtrack which also do their part in giving cues as to where the objects are and if the player is close, really help you immerse into the atmosphere and art style of Machinarium.