Trying to find an item - see sketch please

(mods if this is in the wrong forum, my apologies and please move it).

Hi all,

I'm trying to find some sort of a "power bus" where I can plug in one PCI power cable (from power supply to board) then branch off and plug in HDD power into the rest of the sockets (sort of like a "Y cable" on a PC board)... something like the sketch below.

The connectors are, of course, standard Molex HDD / PCI / Video Card type connectors (although they don't have to be - I can make custom cables).

IDEALLY, there would be several different boards, all the same thing except for a different number of connectors.

Been trying to find something like this and having no luck at all.

If anyone knows where I can buy something like this, I would greatly appreciate it!

(click image for hi-res)
power_bus_img.jpg