Urban Legends Reference Pages: 57 Varieties
http://www.snopes.com/business/hidden/heinz57.asp
"By the time the H. J. Heinz company celebrated its 100th anniversary in 1969 its product line included more than 1,100 items, but over the years the number 57 had permeated almost every aspect of the Heinz corporate culture."
Heinz- Consumer FAQs -What is the significance of "57"?
http://www.heinz.com/Consumer_faq.aspx#Miscellaneous%20Questions%20about%20H.J.%20Heinz%20Company
Although there were many more than 57 foods in production at the time, because the numbers "5" and "7" held a special significance for him and his wife, he adopted the slogan "57 Varieties."
The Straight Dope: Why does Heinz ketchup say "57 varieties"? I only see one variety
http://www.straightdope.com/classics/a1_195
"The number 57 has mystical significance to the Heinz company, but it has never had much to do with reality."