Some one was looking for a nice camera case for their X100 recently. I couldn't find that thread. In any case, Gariz makes some seemingly nice cases that allow for access to the battery compartment without the removal of the half case. Take a look, if interested:
http://m.gariz.com/product/detail.html?product_no=372&cate_no=245&display_group=1
http://m.gariz.com/product/detail.html?product_no=372&cate_no=245&display_group=1