It will depend on the db you are using, but if your db supports case statements, you could do something like this (I have assumed the fields you mention are strings as they all have leading zeroes in their values)...
Code:
SELECT myFieldVal, CASE WHEN myFieldVal = '004' THEN -1 ELSE 0 END AS myOrder
FROM myTable ORDER BY myOrder, myFieldVal;
HTH,
Chris