Originally posted by Drought
Assuming you have Flash, do the following:
1) In Maya, render out as Targa. I imagine other file formats like .IFF work, but I have only tested with Targa files.
2) Download Virtual Dub (Google for it, it's free).
3) Open the first frame of your animation in Virtual Dub, and it will open the entire animation.
4) Save out as an AVI.
5) Import into Flash and save out as an SWF file.
Hope that helps.