Much like a child under the age of 5, I like to stick things in my mouth and chew on them. At work, I use a lot of office supplies: paper clips (both metal and plastic), binder clips, pens, etc. Today I found the Best Thing to Chew On. It's the biodegradable flatware from the cafeteria. First, it tastes like ancient Fritos. Second, it's a bit soft, it has some give to it so you can really get your teeth into it. I'm fond of all of them - forks, knives, spoons, they're all great.
Recommended action: find some biodegradable flatware and give it a try. If it is too hard, I wouldn't try chewing on it too much, but I don't think you'll be disappointed.
UPDATE, 5pm: Okay, I've been chewing these things all day and I think I've swallowed quite a bit of it and it's kind of giving me a stomach ache.