Machinarium

Created by independent Czech developers Amanita, Machinarium is a deceptively immersive point-and-click adventure game, notable not only for its pitch-perfect soundtrack but for the beautifully considered art direction. It is completely delightful and does great things for a medium often unfairly ignored or flat-out derided in design circles.
The first three stages can be trialled online, after which the full game can be bought (for both Mac/PC) which includes the wonderful Tomáš Dvořák soundtrack.

www.machinarium.com