Well, it used to be
Nine Inch Nails - Hurt. But since I'm feeling better nowadays a lot of songs could apply.
Some of Aphex Twins ambient works would do fine for example. First
Parallel Stripes, in which people may contemplate or something, and when the coffin lowers
Shiny Metal Rods, or
Depeche Mode - Home. Hmm, I need to write that down one day.
Sure, I myself may be dead, but I know what impact funerals and their songs (moods) can have on a person. When my mother passed they played
Brian Eno's Prophecy Theme Made quite an impression on people, including myself ofcourse. It turned the whole ceremonial drag into something special.