Thyme
Thyme has been used by man for a long time, actually as long as some 6000 years. We are used with thyme in cooking but when the herb first came into use, it was popular to have in incense and was associated by the Greeks with courage. In medieval Europe they lay Thyme under the pillow when the herb was said to provide a safe sleep and keep the nightmares away.
The scent is sweet, herb and can be experienced somewhat medical.