Now used on nights out as a discreet indication to friends of potential men whom are worthy of a look and possibly even a smile. It tends to replace the word 'fit' which in our eyes is too obvious, tacky and lacks any element of subtley.
In addition - Power Bump refers to the elite members of the bump force, who are so attactive that they take our breath away. Generally these are celebrities and basically; exceedingly good looking - in every way. Almost everyone agrees on power bumps.