Poor sleep has been acknowledged as an increasingly prevalent global health concern, however, how to design for promoting sleep is relatively underexplored. We propose neurofeedback technology may potentially facilitate restfulness and sleep onset, and we explore this through the creation and study of "Inter-Dream", a novel multisensory interactive artistic experience driven by neurofeedback. Twelve participants individually rested, augmented by Inter-Dream. Results demonstrated: statistically significant decreases in pre-sleep cognitive arousal (p = .01), negative emotion (p = .008), and negative affect (p = .004). EEG readings were also indicative of restorative restfulness and cognitive stillness, while interview responses described experiences of mindfulness and playful self-exploration. Taken together, our work highlights neurofeedback as a potential pathway for future research in the promotion of sleep, while also suggesting strategies for designing towards this within the context of pre-sleep.