Shiverware Musix for iOS Deal
Shiverware has announced a limited time deal for Musix, a fully-customizable multiple-layout isomorphic musical keyboard.
For every 100 twitter followers @Shiverware gets they will give Musix away free for a day (normally $4.99).
So, if they get 100 followers Musix will be free on Friday (20th), if they get 1000 followers, Musix will be free for 10 days.
Note that right now, the app is priced at $0.99, until tomorrow.
More information: Shiverware