I'm researching, doing a lot of searching on this topic. Details are a little hard to come by, with all the different models I have a 60GB (thick) 5th Gen. Goal is to add a 128 or 256GB drive + new battery + thinnest possible housing. I'm not going to use Rockbox. What memory type is best for this application? CF? SD? mSATA? (it seems that mSATA would be the best for repurposing down the road) What are my options for slimming down the case? Can I go with a full 6th-Gen slim housing? Battery - I think stock was 600mAh - are people using 580mAh? Should I consider upgrading any other internals? Display/Logic board? If I upgrade the logic board, could I use one that supports iTunes Playlist Folders?