How would you extend the life of an event?

Events are momentary in time yet their memory, good or bad, can linger for days, weeks, months, and even years.  I think that this is one reason why detail observation for great event planning is so important in ways that we might not even realize.  A small detail at the event might trigger a lasting memory that the client may refer to long after the event has taken place.  So, what would you do to keep that memory alive and working to your advantage?