Freevideoconversion is a free web service that will help you to convert videos into different formats. It is very simple and easy to use anybody. No sign up is required for using it.
To convert videos simply upload your videos in freevideoconversion website select your format and convert it. It currently supports 3gp, avi, mpg, mpeg, mpe4, mov, m4a, mj2, flv, wmv, mp4, ogg, webm formats. It converts files upto 40 MB only.