What the H-E-double hockey sticks is that ungainly thing on top of this other Sony camcorder, you ask? A number of Sony camcorders include built-in projectors that can project your video on a screen or wall as big as 100 inches diagonally. But, you won't hear anything since the camcorder has no speaker. So, this bulbous attachment is a 360-degree speaker ($70) that slides into the camcorder's hot shoe. In the photo, the speaker is slid into the projector-equipped HDR-J710V, which will be available in March for around $1,300.