no (mostly because I've never prepared any, and because Japanese rice is so different from any other rice I've ever seen or tasted--and not always in a good way). but one of my favourites is avocado with salmon sashimi rolled around it. I don't know what the name is.
it's just avocado cut into a thin wedge shape, or just a long shape, and a strip of salmon rolled around it. I think it tastes great.