I've recently published my first Windows Phone application, Combinator. It's a very simple Hacker News client and it's completely free.
Download Combinator v1.0 (Marketplace): http://windowsphone.com/s?appid=a5275a3f-6611-48f6-bd62-7382eda4c028
Download Combinator v1.1 (.xap file): http://www.mediafire.com/?s8m1wch8dj8wpk9
Thank you for your feedback.