The Scrabble Reference is an ebook I've created which allows Scrabble players to easily check if words are legal, to suggest longer words or sub-anagrams given a word and to show what words can be made given some letters (up to 15 letters).
There are two versions, TWL and SOWPODS (TWL is used in the USA, Canada, Thailand and Israel and SOWPODS in the rest of the world)
The ebook is in the Mobipocket format which deals with running the ebooks on all devices - PDAs, mobile phones, Blackberries etc so you just need to transform the input to suitable Mobipocket markup, compile the ebook and their client does the rest.
I must admit to not being interested in Scrabble, but of course I am interested in XSLT, and given the list of words allowed in Scrabble I thought I should turn them into a product - one that you can run on your phone seems perfect.
Generating the ebook was very straightforward - list of strings in, markup out... XSLT 2.0 is ideal for the task.