Sex is not a necessary ingredient for a winning viral. You can substitute quality or relevance any day.
Take mountaineering gear maker Mammut, which has drawn some nice attention through the personage of an 85-year-old British lady, Mary Woodbridge. In a series of videos on her site, Mary details her plans to climb Mount Everest along with her Dachsund Daisy. Mammut also placed help wanted ads with copy like "85 year old British Lady plans ascent to Mount Everest. Need advice and sponsoring," and even infiltrated mountain climbing discussion boards -- a decidedly risky move that appears to have paid off in this case. Now, Mammut agency Spillmann/Felser/Leo Burnett in Zurich Switzerland has put Mary in some print executions.
See Adland's coverage for further details.