Embed Video
YouTube, Flickr Video, Google Video, and Vimeo
Then use (:youtube whatever:) markup where "whatever" is the funny unique code for the movie.
So if your movie's url is:
http://youtube.com/watch?v=tiljk_MemVM
then you enter (:youtube tiljk_MemVM:) to embed.
The same general rule applies to Google Video and Vimeo. So these are examples--always use the unique ID for the movie, not the whole url:
(:googlevideo 4250622769233075850:) (:vimeo 128349:)
Screenr
is a special case since the URL is different than the video id. You are allow to use embed html code just like this:
<object classid='clsid:d27cdb6e-ae6d-11cf-96b8-444553540000' codebase='http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=9,0,115,0' width='560' height='345'><param ....</embed></object>