For 80mm radiators, I did search Frozencpu and newegg, as well as Petra's and jabtech, and the only ones I found were the two I listed, and a "Glacial" one I'd never heard of, and don't particularly trust when for the same price I could get the DD or Swiftech I've at least heard of..
I really like the idea, Graystar, but it's not feasible for my case, at this point. I have an Innovatek Maxi passive radiator mounted on top of the case...actually, your idea might be feasible.
I'll have to take a look at what kind of spacing there is between the fins of the Maxi, and where it is mounted on the case. It might turn the Maxi from passive to active, though I'd have to set mine up to be exhaust instead of intake.
Currently, the Ahanix DVine 4 is lined in sound-deadening material, which may cause a problem in modding that part of the case.
I already have an Apogee installed for the CPU, so there may not be sufficient room, but its worth a shot to check the clearances.
Otherwise, it looks like I'll be buying the DD.