There was an article in the Chicago Tribune today about how an Asian-Indian built their home to reflect the "dualities" they feel as Asian-Americans because, while being raised here, they have a strong attachment to their Indian heritage.
At the center of their home a plague hangs that says: "'Om. Welcome the Gods' -- the Sanskrit word combined with English." They said that 'Om' is a word that's considered the most sacred in the Hindu faith and that it has such a complicated meaning that "volumes have been written to address it importance." I found this site about the word, which says: "It is believed that 'OM' is the mother of all languages. Repetition of 'OM' enables us to maintain mental and emotional calmness, overcome obstacles and enable understanding." That last part sounds like something we all aspire to, though I wonder what they mean by the "mother of all languages."
ॐ Om or aum is considered to be the primal sound out of which the universe and everything came. You see its representation (in Devanagari) on many things. It is even represetned in Unicode (U0950).