I mentioned http://www.simile-widgets.org/timeline/ on #yapc IRC channel this morning, saying it would be nice to see all the old YAPCs as well as the new ones.
The wonderful Philippe Bruhat (BooK) then asked:
14:21 @BooK> ranguard: http://www.yapceurope.org/events/timeline.html # is that what you had in mind?
How cool is that! - there really have been a few conferences - how many do you remember?