I don't post much and I'm not sure if this is already a well known feature or not, but thought I'd mention it in case. I think everybody knows that if you swipe your finger across the message in Messages, it will bring you to the next or previous message. However, I just found out if you swipe your finger across the header portion with the subject/from fields, it will bring you to the next or previous message in the Thread. Very handy!