The first miniature I finished after the Lead Painter's League was an Imperial Battle Robot- the spitting image of this guy from the 40K Rogue Trader rulebook:
The robot was sculpted by a fellow on the 'Oldhammer Community' Facebook group (it may have actually been Oldhammer Trading) and was offered up for sale a couple months ago. I painted the Rogue Trader era Inquisitor a couple years back- the antennae on the robot's head reminded me of the peculiar backpack so I thought they'd make a good pair. I imagine the Inquisitor to be wearing a pre-crusade era powered armor that has been maintained in a stasis field when not in use, and the robot has seen some wear and tear over the millennia.
'People don't make 'em like they used to" he says to his acolytes.