To get a copy of a movie off Gnutella, for example, a user need only double-click and wait for the download, while videotapes require setting up multiple VCRs.

FORBES: Gnutella Could Make Moviemakers Cry

Multiple closures makes gathering assets in new funds more difficult as investors take a wait and see attitude.

FORBES: ETFs Come and Go by the Dozen

Those form a growing part of the market, and it's particularly tricky for the Blockbuster's business model to compete with multiple episodes and box sets, particularly when its offer either requires a trip to the shops or a wait for the post.

BBC: Blockbusted