I was using "Reader sets price" for "The Docks". On review, I don't think this is working and will be switching to 99c fairly shortly.
The "Reader sets price option" seems to restrict your audience without providing many advantages. The first issue is that most offers on Smashwords rely on coupons, which can't be generated for books using "Reader sets Price". At the same time, you can't link "Reader sets price" books to the free ebook directories and users still need a Smashwords account to download it while free books can be accessed by anyone. Some Smashwords readers I spoke to skip over books with this payment type because trying to work out how much to pay is an extra step between them and the book.
If there was a tip jar option on the author page, I'd just make the book free and link back to it. As it is, I'll standardise it as 99c, and then liberally distribute coupons.
The other issue is that I have seen a cover that would fit "The Docks" very well. It actually shows a scene from the book (by complete co-incidence) and was done by a professional cover artist. It is a lot better than the one it curently has. The downside? As it's been premade it's part of the artist's portfolio already so there's every chance people will have seen it. To be honest, that doesn't seem like such a downside, compared to having a better cover.