Easily still my favorite intro of any series ever made.
Delia Derbyshire made a song that in the most ironic use of the phrase is completely timeless. Considering that the first version of this was made in 1962. The BBC left her in a room with a heap of synthesizers (The BBC Radiophonic Workshop) and said go nuts. This was the result.
To this day, a favorite and I have all the themes (apart from the modern ones) on my iTunes.
