Na nach nachma nachman meuman is how the song goes. Is there a meaning behind the song other than than Nachman is from Uman? What is reason given for singing this song? Why do some feel such a strong need to publicize it?
Na Nach Breslovers (as opposed to all breslovers) chant this "song" based off a story that a letter fell from heaven, this letter was found by R Yisroel Ber Odesser. The letters contents said:
"It was very difficult for me to come down to you my precious student to tell you that I had pleasure very much from your devotion and upon you I said my fire will burn until Messiah is coming be strong and courageous in your devotion Na Nach Nachma Nachman Meuman And with this I will reveal to you a secret and it is: Full and heaped up from one extreme to another extreme And with the strengthening of your devotion you will understand it and a sign The 17th of Tammuz they will say that you don't fast". (source: http://en.wikipedia.org/wiki/Na_Nach_Nachma_Nachman_Meuman)
Breslovers sing this with the belief that this "song" hastens the redemption. This song also aides meditation.