Master study - JW Waterhouse 'My Sweet Rose' - I know alot of people don't consider him a master (maybe they do, I don't know), but I absolutely ADORE the pre raphaelites. I've never done a master study before and I loved doing this. Took me about 1hr45mins and isn't finished obviously, but I didn't use layers or anything and used a semi opaque brush for the whole thing. Mostly didn't colour pick - just did at times when I forgot!
Plus here's a link to the screencast of it - was done on screentoaster, so its a bit jumpy, but shows how i did it. If its remotely interesting! (let me know if it doesn't work)