I believe that some people use a diluted bleach solution to treat various moulds. Regular Clorox 6 parts: 100 parts water.

Anybody else have any suggestions

Mold and mildew disease is common on tomato plants, especially in overly wet weather or high humidity. Just as with the other common air borne diseases there is no 'cure' just controls to limit it until harvest. There are any number of recommended control sprays available and Daconil is only one of them so when one thing doesn't appear to be working you try something else.

I personally find the copper and sulfur based powder form fungicides to be slightly more effective for molds and even some of the rose controls for black spot on roses can help. The goal is to dry out the leaf surface and change the pH on the leaf surface so mold sporulation can't happen and the mold dies. Plus this is one of those situations where drastic pruning can be of help. But once it is established it is there for the life of the plant so all you can do is make the best of it.

As antipodean mentioned there is some discussion on another tomato forum (Tomatoville) about using chlorine bleach spray for Gray Mold (what you have) control that offers anecdotal reports of success with it. But the method has very specific mixture ratios and application requirements as well as some really drastic side effects on the plant that you have to evaluate and decide if acceptable to you.

Dave