Tibetan Buddhists believe that saying the mantra (prayer), Om Mani Padme Hum, out loud or silently to oneself, invokes the powerful benevolent attention and blessings of Chenrezig, the embodiment of compassion. Viewing the written form of the mantra is said to have the same effect.
OM (ohm) MA (mah) NI (nee) PAD (pahd) ME (may) HUM (hum)
For more on the specific meanings and definitions about this mantra please visit http://www.dharma-haven.org/tibetan/meaning-of-om-mani-padme-hung.htm they have some really good information there.
I found this mantra several years ago and printed it out. I would only think of it occasionally. I read this mantra in a book today and put my print out on a wall and was chanting off and on. Now I found this on a delightful blog. I think this is what you would call a sign and I will be chanting this mantra a lot more often! When something calls you, you should listen, I am still learning this.