To build a folly is essentially to do something a second time, something at an inopportune moment. That something is always the memory of something forgotten, about which we can paradoxically say "There it is again."
Follies were misunderstood, purposeless constructions. They were often only small, extravagant gestures in a garden, easily whisking off the imagination to distant lands, a sort of time capsule built to awaken the memory and induce surprise in passers-by. They marked locations, organized secondary paths in a park, or simply predicted the arrival of better times—a demarcation, a sacred spot, a mysterious trail, a hill whose tragic rocky nature begged for a tower, a party, or the arrival of summer.
“It is demonstrably true that things cannot be other than as they are. For, everything having been made for a purpose, everything is necessarily for the best purpose.” — Professor Pangloss
Jakob Nielsen says that Flash is “99% bad.” I have to agree. Flash always reduces usability.
On the other hand, every time I read Jakob Nielsen, I get this feeling that he really doesn’t appreciate that usability is not the most important thing on earth. Sure, usability is important (I wrote a whole book about it). But it is simply not everyone’s number one priority, nor should it be. You get the feeling that if Mr Nielsen designed a singles bar, it would be well lit, clean, with giant menus printed in Arial 14 point, and you’d never have to wait to get a drink. But nobody would go there, they would all be at Coyote Ugly Saloon pouring beer on each other.