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Hi-res version with shadow (used at sizes 512, 256, 128):
![frescobaldi512](https://f.cloud.github.com/assets/5209500/1460304/57ce785c-4427-11e3-96ad-cb8cf088cd6a.png)

Low-res version with "enhanced F" (used at sizes 32, 16):
![frescobaldi32](https://f.cloud.github.com/assets/5209500/1460305/62d403ca-4427-11e3-9cfe-571b511da860.png)
![frescobaldi16](https://f.cloud.github.com/assets/5209500/1460306/652711a8-4427-11e3-949f-5b74920bfc61.png)