Mobile phone antennas are designed to project a signal in a donut shape, perpendicular to the long axis of the antenna. If you are holding your phone in a strange way, such as on its side or upside down, you will hinder the operation of the antenna. [wiki
Thanks to /u/AwayThrow1984 for his amazing collection! I know the pain of those who browse the sub on mobile and can't view the collection, so I have started uploading them to imgur. Here's the first 150!
My wi[f]e sent me this from work while I am out of town on a business trip...can't wait to get home!!! [watersport] (sound in comments for mobile users.)