Bad Days is a neon slice of nostalgia. Excavation focuses on the mid-'90s, specifically the albums Transmissions from the Satellite Heart and Clouds Taste Metallic. For those fans -- and there are lots of them -- who believe this period represents the Lips' peak as avant-pop masters, this EP is essential. Demos of "She Don't Use Jelly" and "This Here Giraffe" offer a peek behind Wayne Coyne's curtain. Then there's the hurdy-gurdy psychedelia of "Girl With Hair Like an Explosion." Great stuff.