Riddle Dude by One Month Games
for Windows Phone 7
http://onemonthgames.com/games/riddle-dude/
Genre: Trivia
The Riddle Dude is a daily interactive brain teaser for the love of riddles. You should check this app daily for new riddles and submit guesses.
This app is an RSS feed from the original Riddle Dude website at http://riddledude.com/
Link: Zune Marketplace (Now available!)
Screenshot: