This week, I 'ave bin mostly playin: Plants Vs. Zombies.
This is because it is awesome.
The basic idea is fairly obvious from the title; the only clarification required is that you are on the side of the plants. Or, more accurately, the plants are on the side of you, since they are all that stands between the zombies and a delicious brains-croque-monsieur, of which the principle ingredient is you.
In practice, the game is not a million miles away from Desktop Tower Defense, which I've mentioned before, except that the zombies can only arrive from one direction, and the available defences are far more varied and interesting. And funny, as well, which is impressive. Being able to write 50 biographies for different zombie-killing plants and make them all amusing (to say nothing of the descriptions of the dozens of zombie sub-sets themselves) requires a special kind of creativity.
Oh, and it also has one of the best credit sequences in living memory, though you probably have to experience the game to appreciate it fully. Still, J-Pop + shambling undead? Sign me the fuck up!
I acquired this genius for the bargain price of eight quid from Steam, and it was worth every penny. Alternatively, there are demos you can download. I recommend that you do. The only obvious flaw with the game is that it's kinda easy; I only had my brains eaten four times over the course of the whole thing, and three of those were on the final set of levels (stoopid bungee zombies!). Regardless, it still took me most of a day to complete (and there are many bonus levels I haven't gotten around to yet), and for the price of less than four pints (which continues to be the only sensible way to measure fiscal strain), you could do a whole lot worse.