According to the About text Eucalyptus relies on a customized version of libhyphenate, plus a number of other open components (including LinuxLibertine as the display typeface).
I love the look of Eucalyptus and haven't seen any other reader that comes close (particularly at the iPhone/iPod screen size and resolution, and ESPECIALLY given that as far as I can tell they use the .txt versions of the Gutenberg files). It's not that they've sacrificed the right goats to the gods of text presentation magic, it's just that they actually give a damn what the output looks like.
I love the look of Eucalyptus and haven't seen any other reader that comes close (particularly at the iPhone/iPod screen size and resolution, and ESPECIALLY given that as far as I can tell they use the .txt versions of the Gutenberg files). It's not that they've sacrificed the right goats to the gods of text presentation magic, it's just that they actually give a damn what the output looks like.