Real one. Parents have REAL candles on it that we light a couple of times (tonight being one) during the season. We read a Christmas Carol passages and other readings around it with various friends and neighbors all reading. My mom started doing this back in 1972 when they had the first oil embargo and they wanted us all to conserve energy. This was her solution. It stuck and we have been doing it ever since. We have a real one here too, but use LED lights. We cut it at a place run by an 80 yr. old gentleman, who I love giving my $25 to each year.
Here are pics from one we did last year or year before:
