I'm thinking that an animated aquarium would be a fun little project for the Windows Phone so I've decided to port the WinForms version I did awhile back. After a couple of fruitless hours of trying to wrestle silverlight to do animated images I thought to myself "Wait a minute. This has to be a lot easier in DirectX".
Lo and behold it is because of course frame animation is a big part of game programming. Got the first version whipped up in a just a few hours.