2 years ago I reached 700k [http://www.mmo-champion.com/threads/...ou-want-Blizz!] before the great lootgold nerf (5.0.4, before this: ~14k each ID). Weekly farm route from then on was only 1.5-2k lootgold (~4.5h). But thanks to AoE Loot and Potions of Luck, Troves of the Thunderking and all those Keys that open chests with gold, I made it to 1.000.000g.
Troves of the Thunderking proved to be the most fun way to do this. I guess I never missed a key (each week, ~70+ since 5.2) since 5.2, because it's just a few minutes of visiting the island. A good way to improve the perfect farm route was grinding 15+ runs back to back. All in all you can get 650g+ on average from each run.
And now, almost 2 years after 5.0.4 release (oh the irony), I crossed the 1m mark. Didn't expect this at all after the nerf to old content, even though you could get ~4k from Cata25hc (every week, raid that needs to be organized a bit). I don't know if I (still) have any competition when it comes to this, especially since there is no AV past 200k (and that's account wide), but I guess some of the Potion-of-Luck-Farmers made a huge leap during this Xpac.
I'm not begging for a new AV, just proving that it can be done.
And for those who wonder about an average gold per hour: 1k can easily be achieved in old content with speed clearruns (full group with only loot gold in mind). Same goes for Potion of Luck + Guo Lai Halls.