Giving a user, superuser privledges

[Statux <statux bigfoot com>]

I know this gets mentioned now and then, but I seem to have forgotten to
save a copy of an email that explains it.

How does one go about giving a user superuser privledges (like, say
there's an account called 'peach' which is a regular user, but peach runs
the machine in question as well, etc)

I know it involves /etc/passwd, /etc/group, etc.. and you have to run
pwconv and something else or whatever..

help?:)

Thanks

-- 
-Statux