Is there an easy way to loop through every stored procedure in a database and create a file containing all of the SP code?

By joining sysobject and syscomments table we can get your desired results,
run this query in Query Analyzer (with result in text mode)....
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SELECT dbo.syscomments.text, dbo.sysobjects.name
FROM dbo.syscomments INNER JOIN
dbo.sysobjects ON dbo.syscomments.id = dbo.sysobjects.id
WHERE (dbo.sysobjects.xtype = 'p')
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