On its own, the new Sony Reader Digital Book, which promises several improvements over the earlier Sony Reader, can carry the collected works of Stephen King with plenty of room left over. The Reader’s onboard storage is enough to keep about 160 eBook titles, on average, and capacity can be further boosted through memory cards. Avid readers can now take an entire stack of New York Times bestsellers on vacations or business trips without having to worry about overloading their suitcases, thanks to this week’s launch of the latest Reader Digital Book from Sony.