Hidden Folks [Steam store page]
A bit like Where's Waldo, but sometimes you have to click (or drag) on one or more items to reveal the person you're looking for. Each target has a hint though, which gives you an idea of the area or action you need to find it.

I was surprised at how expansive some of these drawings are - you can pan around, and often it helps to zoom in rather than staying at max distance, especially when looking for a small object. And with the complexity of these drawings it will probably take you at least a few hours to find all the targets.

Machinarium [Steam store page]
Nicely drawn point and click - but the puzzles are too obtuse for their own good. The hint button is hidden behind a long minigame with a key that shoots bullets (which the game doesn't mention and the minigame can't be completed without them)