Desktop Tower Defense is a flash based Tower Defense Game , located at http://www.handdrawngames.com/DesktopTD/Game.asp. The game gains its name because the playing field is an image of a desktop (in the literal sense), and perhaps because it has to be called something. Apparently, Tower Defense started as a subset of themed fantasy war games, but Desktop Tower Defense is rather abstract. The enemies, or "creeps" are simple geometric objects that flow from one side of the screen to the other, with a few sound effects. The player's way of stopping them is to build towers, that shoot at and kill the creeps, and slow them down as they negotiate the maze. Fifty consecutive waves go through the maze, some with special powers, and some being much tougher to kill, with each wave being harder to kill. Killing enemies gains the player money, that they can use to build more towers. The game is a prototypical simple, addictive flash game.
And the game is very addictive, especially as the player tries to find out the best formula for their maze. The first few days I played the game, I played it for hours until I had Open Eyed Visuals of the swarming waves of creeps. My obsession faded when I finally viewed other people's replays, and learned the set-up for beating the game on the medium difficulty level. Currently, when I play the game, it is usually on the "random" setting, which is a good pasttime, without too much concern over getting a high score.
As a game, I find it very fun, but it is in some ways limited, because past a certain point, there is no way to go beyond or above the formula for winning. Many games that I find interesting involve an aspect of strategic transcendence, where a skilled player puts together several small factors that interact exponentially, allowing a player to do much better than would at first be guessed. The game doesn't have any way to combine elements like this, which is why its replay value is somewhat limited. But then, it still fulfills the purpose of a flash game very well.