file splitting

[Karl Hasselstrom <kha@treskal.com>]

I'm looking for one or more programs that can do the following:

1. Split an X byte file into n pieces of X/k bytes each (n >= k), such
   that any k pieces suffice to reconstruct the file.

2. Split an X byte file into n pieces of X bytes each, such that any k
   pieces suffice to reconstruct the file (n >= k), but no group of at
   most k-1 pieces convey any information about the file contents
   whatsoever.

3. Split an X byte file into n pieces of X/k bytes each (n >= k), such
   that any k pieces suffice to reconstruct the file, but no group of
   at most k-1 pieces convey any information about the file contents
   (under the assumption that some cryptographic algorithm is
   unbreakable).

-- 
Karl Hasselström, kha@treskal.com
      www.treskal.com/kalle