If you're a gamer, you'll immediately peg Breaking the Tower as a bonsai version of The Settlers - you don't directly control the little dudes wandering around on the map, but instead just plonk down buildings for the little dudes to interact with.
If you're not a gamer then this'll all be new to you, but I strongly suggest you give Breaking the Tower a try anyway. It also strikes me as a very good game to point your non-gaming loved ones at, to give them an easily-digested first step into "proper" games, instead of the little Flash "casual" games which Breaking the Tower initially resembles.
Breaking the Tower has enough depth to be interesting, but not enough to be overwhelming, thanks to a variety of extreme simplifications of the usual dynamics of a game of this type. The little dudes, for instance, only consume food when they're created in a "Dwelling"; you need five food per dude, but after they appear they can live forever without taking another bite.
And there are no baroquely complex interrelationships to memorise. Gamers are used to taking a long and painful time to figure out that they need exactly three Baby Skinners per Novelty Shower-Curtain Maker, and that you don't need to build any Shin Guards if you haven't also researched Coffee-Table Technology. The few elements in Breaking the Tower, in contrast, are all right there in front of you all of the time.
So you still get the fun of figuring out how the parts of the game fit together, but you don't have to look up a FAQ to find out why your Peasants keep chopping the heads off all of your Nobles right after you add a Cakeworks to your Palace.
And despite its simplicity, Breaking the Tower still has the very soul of a good strategy game: Every time you think you've found something unbalanced that lets you just Build Lots of X to Win (Tons of warriors! No warriors, but giant population! Sweep the leg!), you'll find that strategy screws something else up. So you have to go for a more balanced approach.
Breaking the Tower is also very slow-paced. It's quite hard to finish a game - win or lose - in less than half an hour, and it's easy to take well over an hour to win. But you don't actually have to do a great deal in that time.
This is surprisingly great. It lets experienced gamers put a strategy into motion and then minimise the browser window and come back after ten minutes to see what's happened. And it lets complete newbies take all the time they need, without some awkward pause-the-game-and-issue-orders system.
(And yes, it also lets you keep on playing after you win, so you can do that other nostalgic staple, leaving a game running overnight to see what ghastly fate has befallen the little computer people by morning.)