So the people at diablo market watch have come up with a pretty cool app. Basically it will allow you to see what items are selling for in the auction house and what items are currently in demand. This is awesome for knowing what to sell your items for. Check it out.
http://diablo3marketwatch.com/I wasnt sure if this should be in confirmed guides or submissions. Only reason i decided on posting it here was this should be in the guides section for members.