Given a url to a somevid.com video like: http://somevid.com/YvEkX82q2zH9Mbo6y8VX. Here's how you can rearrange the url to download the video as an mp4:
wget $(echo "http://somevid.com/YvEkX82q2zH9Mbo6y8VX" | sed -e "s/com\/\(.*\)/com\/transcodes\/\1?format=1\&chunk=0/") -O output.mp4
Probably if it's a long video you'll need to increment the chunk=0 to chunk=1 and so on and then stitch the video together.