Photoshop: Reference image holder as a panel

As I work with hundreds of images every day and ALWAYS use a reference image on the side for correct colour from different skin colors, it would be great to have a panel you can dock where you can have your different images you use as reference. I think most proimaging services could use this to greatly improve workspeed etc. Now I have to have a separate floating window, and it always gets in the way, and even worse, when I open a new batch of images they start docking into the reference image I have open...