Despite being a quite controversially discussed project, the expo.2000 for me was indeed something special.
Personally I consider it well worth the effort that has been put into it - though not everything was perfect.
But what or who is?
One of the things I liked best were the (unfortunately few) pavilions with interactive displays.
Probably my favourite one was the Swedish display of user-triggered sights and sounds which made quite a change from the others, mostly concentrating on passive entertainment.