This is essentially the same effect as my Sinedot Photoshop Filter. I just did a quick conversion to AfterFx because it's so easy :)
Don't ask me what it's good for. If you actually had a good usage for it please mail me and let me know. I'd be very interested in hearing and especially seeing what you used it for.
Sinedots for Windows (25kb, for AfterFx compatible).
(last changed on 6th of october, 2003)
For a preview on how this effect can look like here is an encoded video: