video sequence as texture?

i’d like to use the camera-in-front-of-textured-plane method for making this video but that would mean i couldn’t use the ever so convenient VSE.

is it possible to set the sequence as a texture? i’d like to add special effects such as halos and whatnot.

i’d just rather not render the whole vid then import back into blender then re-render with the FX. i like the flexibility in case i need to edit the original video.

thanks

EDIT: even better, is it possible to add a SCENE to a sequence with and alpha background?

edit:sorry, i’ve recently discovered alpha over/under/over drop. i guess i wont be needing this thread any more.