kat: I am told one should burn other herbs with sage (white sage, the very strong stuff new agers smudge with) because it can leave a "psychic void" (or so it was put to me). That is why a lot of the bundles you buy are mixed with juniper, sweetgrass, or lavender...

too much sage smoke is a respiratory irritant. There is this one guy who likes to smudge the whole audience with a sage bundle before our concert every year at Starwood; I finally had to stop him doing it because one year it was so bad people with breathing difficulties (atsthmatics etc) had to leave. And I choked on the second verse of my only solo of the night!