It's interesting to see a private process like this; I bet someday soon, you'll be able to "watch" a writer type and edit an entire novel in real-ish time as an e-book extra feature.
If you're more of a do-er than an observer, you can write magnetic poetry over here. There are other collaborators, though, so you might find a word has been stolen from your poem by someone else on the internet.
(The Matt Bell link is from Galleycat; hat tip to Book Patrol for the Magnetic Poetry link.)