How the TempDB becomes Full?

• DBCC CHECKDB will perform its work in tempdb
• DBCC DBREINDEX or similar DBCC commands with "Sort in Tempdb" option can make the tempdb full
• Large resultsets involving unions, order by, group by, joins, temp tables etc. can also fill up tempdb
• Any transactions left uncommitted and not rolled back can leave objects orphaned in tempdb
• An ODBC DSN with the option 'Create  temporary stored procedures' set can leave objects in tempdb.