Totally different game of course, but this reminded me of Katamari Damacy! In many levels you start tiny in a room somewhere, and have to roll up paper clips and thumb tacks in order to grow and roll up successively larger things, while avoiding gigantic pets, and so on. Apart from being hilarious and sometimes challenging, I also found it an interesting psychological effect to come back to the same place when you're 100 times larger, now able to roll up humans, cars, the entire house... :)

Katamari is a casual game (I prefer this genre) but now I wonder if there would be some way to make a more "simulationist" game that uses this scaling effect somehow.