Do you need a ticket number or unique ID for your SharePoint List or Library?
UPDATE http://spandps.com/2011/03/09/unique-alphanumeric-list-ids-via-spd-workflow-and-calculated-columns-sharepoint-sp2010-in/
Use Document ID
http://blogs.msdn.com/b/ecm/archive/2011/10/12/document-id-in-sharepoint-server-2010.aspx
Old Solution ( Doesn't Auto Update)
Create a new calculated column with the following formula
=TEXT(1000+ID,"0")
where ID is the hidden ID column created by default and 1000 is the offset
The data type returned from this formula is: single line of text or number
