Daily my development is with Django and it was great to find that the documentation, which is built with Sphinx, can easily generate very nice epub output like this:
Here's how to generate your own:
The output is in _build/Django.epub which you then drag to iTunes to install on an iPad.
pip install -U sphinx
svn co http://code.djangoproject.com/svn/django/trunk/ djangosvn
The only thing missing is a cover image.
For your convenience, I've stuck a copy here.
Update: built Python 2.7 doc as epub
After that success I had a shot at building the Python documentation. The sphinx that comes with the python source is old and doesn't include the epub builder so I used a separate sphinx. All seemed to go well:
Here's the command line:
For your convenience I've put a copy here: Python 2.7 epub documentation. (That's a goo.gl shortened url by the way).
sphinx-build -b epub -d build/doctrees . build/epub
The output looks excellent on an iPad, it's 3,943 pages at normal font size and the iPad does groan a little but it is quite usable. epub is much much better than pdf for reading on tablets.