C-x C-e on numbers

[Alfred M. Szmidt]

Currently, when evaluating a number, emacs will print the decimal,
octal, hexadecimal, and charachter of said number.

  42 C-x C-e ==> 42 (#o52, #x2a, ?*)

It would be useful, if the output would also include the binary
representation of the number.  Or at least somehow enable such
behaviour.  I.e., 

  42 C-x C-e ==> 42 (#b101010, #o52, #x2a, ?*)

It would also be useful to change the printed representation of a
number, so that the above would become,

  #o52 C-x C-e ==> #x2a (#b101010, 42, #o52, ?*)

But this would probobly require some more work.