I read an article today about driving and moods - and they recommend using peppermint for alertness. You should try our Mood-scent Energy or Happiness - both fantastic for helping keep you alert and alive on the drive!
http://www.moods-inc.com
Check out the article for other great research and ideas:
http://health.yahoo.com/tips/do-you-have-good-driving-scents/realage--4929.html