I was in N California for the Annular Eclipse last month and several people had the shoebox pinhole camera setup. For an eclipse that might work okay, but the image was less than 1/2" tall. Trying to view something very small like Venus crossing the sun would probably be impossible, or at least not very satisfying. Even using my eclipse glasses it was a little difficult to make out the disk of Venus on the sun yesterday. Projecting with a pair of binoculars is the easy way to do this. If you have a telescope with a solar filter that is better, but since most people have binos that is undoubtedly the easiest.