Get server's time in UTC time zone, in ISO 8601 format

Googling for 3 hours has taught me much about Postgres' handling of time, but has not answered the question:

-->  How to get the server's time in UTC time zone ('ZULU'), in ISO 8601 format, by executing a simple SELECT
statement?

This 2-step approach works:
  set time zone 'UTC';
  select current_timestamp;

That does render the actual UTC time (8 hours ahead of US west coast time):
  2010-12-02 00:24:56.284816+00
Note the timezone on the end: +00 (that's a good thing)

Surely there must be a way to do this in a single SELECT.

I tried using "AT TIME ZONE":
  select current_timestamp AT TIME ZONE 'ZULU'
That does indeed give me the UTC time, but without a timezone on the end such as +00 or z or zulu:
  2010-12-02 00:29:05.735597
Note the lack of +00 on end (that's a bad thing)

I'm using Postgres 9 with Mac OS X, using United States UTF-8 settings.

--Basil Bourque