Make a 15 Digit Case Sensitive ID to 18 Digit Case Insensitive ID

Found this one on the developer forums: http://goo.gl/W0vce


Id 
& MID("ABCDEFGHIJKLMNOPQRSTUVWXYZ012345",( 
IF(FIND(MID(Id,1,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,1,0) 
+IF(FIND(MID(Id,2,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,2,0) 
+IF(FIND(MID(Id,3,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,4,0) 
+IF(FIND(MID(Id,4,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,8,0) 
+IF(FIND(MID(Id,5,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,16,0) 
)+1,1) 
& MID("ABCDEFGHIJKLMNOPQRSTUVWXYZ012345",( 
IF(FIND(MID(Id,6,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,1,0) 
+IF(FIND(MID(Id,7,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,2,0) 
+IF(FIND(MID(Id,8,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,4,0) 
+IF(FIND(MID(Id,9,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,8,0) 
+IF(FIND(MID(Id,10,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,16,0) 
)+1,1) 
& MID("ABCDEFGHIJKLMNOPQRSTUVWXYZ012345",( 
IF(FIND(MID(Id,11,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,1,0) 
+IF(FIND(MID(Id,12,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,2,0) 
+IF(FIND(MID(Id,13,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,4,0) 
+IF(FIND(MID(Id,14,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,8,0) 
+IF(FIND(MID(Id,15,1), "ABCDEFGHIJKLMNOPQRSTUVWXYZ")>0,16,0) 
)+1,1)