I don't want to cheer you up or anything but a gopher pulled down 7 of 30 tomato plants before I dug the others up and replanted them in gopher baskets. I'm pretty sure the same gopher is now working on my corn, so I don't think he fell ill to nightshade toxicity. I don't think gophers buy into the whole nightshade thing and I know deer don't because without my electric fence I wouldn't have any tomato plants or tomatoes. Humans can only eat the fruit of the tomato plant but everything else seems to thrive on the whole plant.

http://forums2.gardenweb.com/forums/load/cornucop/msg071530552869.html

Here is a link that might be useful: how to get rid of groundhogs etc

Sounds like it may have been a mountain beaver. They are unique to the west coast. I saw them frequently were I grew up in western WA. They don't move real fast and are usually seen dead on the road. I watched one once clip and drag bunches of large dandelion leaves from the edge of my yard to its burrow(I assume)...it took several trips. It was fun to watch...of course, it wasn't chomping down my garden plants...if it was I might feel differently. I don't know if they would damage your tomatoes. Maybe you could place a ring of chicken wire around the base of your toms for a while.

Here is a link that might be useful: mountain beavers

I caught a glimpse last night. Dark brown, about the size of a hoagie bun. I don't think it had a tail. My kingdom for a garter snake. A real one. Plus it will keep the neighborhood kids out too. ;-)

You got rats. Or maybe a small bunnie.