When it's within a couple hours of bedtime, I find that death metal and thrash pumps me up too much. I need something mellow (but NOT happy) to unwind to. So far, the mellow bands that I listen to at night include: Opeth, Arcane Sun, Katatonia, Lacuna Coil, Anathema, My Dying Bride, Mourning Beloveth, Novermbre.... You get my drift. I'm looking for more suggestions.