Mayumi is easy entertained. Don't get me wrong; she is just as easily dismayed, discouraged, and...yes, devastated. But when she laughes, it is memorable.
Baby Yumi still cannot crawl, and so relies heavily upon whatever items we put on front of her for entertainment (I know, if we didn't put anything in front of her she might go seek it and THEN start to crawl). I keep a couple of baskets full of random things (the more un-toylike, the better) with which she can play.