uniq command

[Lucy Premus <lpremus@METLIFE.COM>]

A few weeks back I had asked if there were a way to count lines that contained a
field that was the same.  Most of the suggestions were to use the uniq command.
I want to say thank you, it was exactly what I needed.  But now I have a related
question.  Is there a way to read lines in a file containing a field thats the
same and output those lines to another file; again without knowing the value of
the field?  For example, my file looks like this

server1 nyho
server2 nyho
server3 nyho
server4 risc
server5 risc
server6 mlb
server7 mlb
server8 mlb
server9 mlb

The result will be 3 files that look as follows:

server1 nyho        server4 risc         server6 mlb
server2 nyho        server5 risc         server7 mlb
server3 nyho                       server8 mlb
                              server9 mlb