[Index] Size, usage, and location of your indexes

Updated my old code, since we were trying to figure out what indexes needed to get moved to the secondary (index) filegroup. You can even filter based off the usage (commented out below)
Standard disclaimer applies. Select the contents of the post, then copy/paste.

SELECT
        o.name AS Table_Name ,
        i.NAME AS Index_Name ,
--        i.type_desc,
		CASE i.type
			WHEN 0 THEN 'Heap'
			WHEN 1 THEN 'C'
			WHEN 2 THEN 'NC'
			ELSE '?' END AS [Type],
        p.rows AS [#Records] ,
        a.total_pages * 8 / 1024 AS [Reserved(mb)] ,
        a.used_pages * 8 / 1024 AS [Used(mb)] ,
        s.user_seeks ,
        s.user_scans ,
        s.user_lookups,
        fg.name, 
        f.name,
        f.physical_name
FROM    sys.indexes AS i
        INNER JOIN sys.partitions AS p 
			ON i.object_id = p.object_id
            AND i.index_id = p.index_id
        INNER JOIN SYS.OBJECTS O 
			ON I.OBJECT_ID = O.OBJECT_ID
        INNER JOIN sys.allocation_units AS a 
			ON ( a.type = 2
				AND p.partition_id = a.container_id
               )
			OR 
				( ( a.type = 1 OR a.type = 3)
				AND p.hobt_id = a.container_id)
        INNER JOIN SYS.DM_DB_INDEX_USAGE_STATS S 
			ON S.OBJECT_ID = I.OBJECT_ID
			AND I.INDEX_ID = S.INDEX_ID
			AND DATABASE_ID = DB_ID(DB_NAME())
			AND o.type_desc NOT IN ( 'SYSTEM_TABLE', 'INTERNAL_TABLE' ) -- No system tables!
		LEFT OUTER JOIN sys.database_files f 
			ON f.data_space_id = a.data_space_id
		LEFT OUTER JOIN sys.filegroups fg 
			ON fg.data_space_id = a.data_space_id
--AND (ISNULL(s.user_seeks, 0) + ISNULL(s.user_scans, 0) + ISNULL(s.user_lookups, 0)) < 100
WHERE   OBJECTPROPERTY(O.OBJECT_ID, 'IsUserTable') = 1
        AND i.TYPE_DESC <> 'HEAP'
        AND i.type <> 1 -- clustered index
ORDER BY o.NAME ,
        i.name