Niamh Sharkey, who I am happy to say wrote a book and designed some wonderful covers for Mercier before she went onto mega-stardom (and before I started here), keeps a nice blog here. Today she posted a wonderful note about keeping ideas in notebooks with some really excellent examples given:
If I am starting a new project and looking for ideas and I get stuck I go back and look through my old notebooks. The Ravenous Beast started as a card design called Ravenous Monsters I painted in 1994. When I first went to Walker Books they spent most of the time looking through my notebooks. Amelia the head designer saw this painting and said mmm… interesting. It started from there.
Definitely worth reading!