Kate -- I have tried it according to the method described in the link Alessandro provides. It works, but not that well. I used a Tetenal 3-bath kit and replaced the colour dev with sepia toner. The resulting slides are way too dense and even several stops' overexposure doesn't improve things much. There is simply too much highlight density in the resulting slides and I think it has to do with the toner interacting with developed silver.
Originally Posted by Kate Mocak
Note that you need to use a slide-developing kit to try this anyway, or home-brew a very active and solventy first-developer and a mild-ish bleach-fix formula. Regular B&W reversal processes use bleaches that absolutely destroy slide film (I have tried this too).
Have a look on my page (www.photosensitive.ca) in the About section for a link to an article on this.