How Do You Feel When A Baby Laughs?

From a comment at Alex Kjerulf’s blog post about Global Belly Laugh Day, I picked up a link to the following video showing a baby laughing from the depths of it’s soul.

[kml_flashembed movie="http://www.youtube.com/v/HttF5HVYtlQ" width="425" height="350" wmode="transparent" /]

When was the last time you laughed this purely?