Remove duplicate records in a table

CREATE TABLE dbo.authors
(
PK_Column INT IDENTITY,
Authorname VARCHAR(50)
)
GO

INSERT dbo.authors(Authorname)
SELECT 'Author1'
UNION ALL SELECT 'Author1'
UNION ALL SELECT 'Author1'
UNION ALL SELECT 'Author2'
UNION ALL SELECT 'Author2'
UNION ALL SELECT 'Author3'
UNION ALL SELECT 'Author3'
UNION ALL SELECT 'Author4'
GO
SELECT * FROM dbo.authors
Go
DELETE authors FROM authors a
LEFT OUTER JOIN
(
SELECT Authorname, pk_column = MIN(PK_Column)
FROM dbo.authors
GROUP BY Authorname
)tbl ON a.pk_column = tbl.pk_column
WHERE tbl.pk_column IS NULL

More details:
http://docs.google.com/View?id=ddwrnq4_3hg8gvfhp