A new idea I'm playing with. What do you think of making a Visual Novel with Construct2? Someone made a demo here: http://www.youtube.com/watch?v=GuQUT00Tsjo
C2 isn't the only option. There is also Ren'Py (http://renpy.org/why.html), a free program specifically designed to create Visual Novels. It creates .exe files though.
Then there's Corona SDK, which specializes in making mobile apps, but can also be used to make ebooks (http://www.anscamobile.com/corona/ebooks/).
The obvious advantage C2 offers over either of these is that it's playable from the Internet, so no need to download anything.
Although, you do have to "point and click" to create events, and since Visual Novels have a lot of text in them, this could get annoying (as opposed to simply typing out code like in Corona or Ren'Py).
What do you think?