I saw a brief review of this game in WIRED and decided to try it out. DTD is dead simple, but addictive. The objective is prevent
swarms of various kinds of land and air critters from cutting through your territory. You have some money to deploy a few weapons, then get more money for each critter terminated. Some weapons cheap, but low performing. Others more expensive. Some weapons work better than others depending on the critter (the little, black bat things are really tough). Kill and build or be killed.
It’s a little like the early PC-versions of WarCraft: Orcs & Humans in terms of interface and rough strategy. Play this game at the risk of developing an obsession that will throughly annoy friends, family and co-workers… until you can suck them in too. There’s not a multi-player version or this game would be even more problematic to productivity.

If you liked that one, try Garden Defense. I have found it fully addicting (even though my family makes fun of me for defending a garden). http://www.iwin.com/download/1735447108562346727/garden-defense-game