If you've never played a tower defense game, now's your chance. Pirates Love Daisies is easy to play, family-friendly, and features a tutorial that walks you through the mechanics of the game. The visual style is nothing short of beautiful (but cute), and the soundscape is excellent. The point, though, is that Pirates Love Daisies is written in HTML5 -- and when you realize those scudding clouds, buzzing flies and droplets of rain are all being rendered by the browser, your mind blows.
That's not to say the game is without issues, though; despite looking the best in Internet Explorer 9 beta 2, it crashed multiple times (see screenshot after the break), and Firefox 4 beta 7 didn't even get past the loading screen. Firefox 4 also had significantly degraded audio, for some reason. Chrome 9 worked just fine, but seemed to use more resources than IE9.