I only have a few. I grudge paying over £5 for a book I've already read just to get it as an ebook! I am very price sensitive though. For example, one of my all time favourites is Ira Levin's This Perfect Day. I've so for bought two other Levin books (I've read them all previously) one in Kindle deal of the day for £0.99, the other for £2.99. Still waiting on my favourite to be reduced from £5.99. I'm sure I'll get it at some point.....