Create a new database
I create new dbs just infrequently enough that I never remember the flags I use when creating the db. In this example, I create a database using the SQL_ASCII character encoding (which is sort of the non-character-encoding character encoding, as opposed to, let's say, UTF8 or LATIN1) and collating/sorting based on the C locale, which is the "no locale" (as opposed to, let's say, en_US or fr_CA):
createdb \
-h myhost \
-U myuser \
--echo \
--owner=myuser \
--locale=C \ # only psql 9.0 and above
--encoding=SQL_ASCII \
my_new_database
Or, from the db:
$ sudo su - postgres
$ psql template0
template1=# create database my_new_database with owner = myuser template = template1
encoding = 'SQL_ASCII' lc_collate = 'C' lc_ctype = 'C';
template1=# \q