Do you often listen to TED talk (www.ted.com). Check out TED Mobile for Windows Phone.
TED Mobile is an unofficial client to listen to TED talks. You can listen to latest talks or create your own favorite talk list. English subtitle is also provided.
Moreover, you can also download talks to view offline later. This is very helpful as you can download your favorite talks using WiFi, then go out and view the talks when you are going outside. These offline talks will save your 3G data usage, while you can still enjoy the talks on the go. You will not have to endure waiting for slow connection as well.
You can also pin the live tile to your start screen to see the latest talk at just a glance.
You can download TED Mobile by this link or using this QR code.