I use NB's Center of Gravity 3 tier system. Sitting here looking at it as I brew a German Roggenbier today. The HLT is at the top, of course. I use an insulated MT in the middle tier, and my boil kettle is at the bottom. During the mash, I use the BK, with about 3 gallons of water and a copper coil in it, as a HERMS setup. That gives me a recirculating mash, which filters the wort. During the mash, the HLT is being used to heat my sparge water, and later, during the boil, it will be used as a source for sanitizer to run through my plate chiller. During the summer, when the tap water isn't as cool as I would like, I simply recirculate the mash through the chiller and back into the BK, until it's getting cool enough, so that another pass through the chiller will have it at a safe pitching temp. That little step adds about 10-15 mins. Not bad, considering how much time it saves me later on, waiting for the wort to get cool enough on its own, to safely pitch.
My system is gas-fired right now, but I am thinking of switching to all-electric, and use a PID controller, which will automate things even more for me.
I have kind of duplicated Blichmann's BrewEasy, I think, and really like the result. Were I to purchase an entire system now, I think I might go with the BrewEasy, but this has been acquired a bit at a time, over several years, and I can't justify getting rid of all of it, to go with Blichmann's setup. (Hmmm. Maybe if I win the lottery!)
I'd love to put a picture of my setup at work, but my computer is down right now, so cutting as pasting is not practical.