zOMG. Made like, 300k in 4 days. And the people I was crewing with didn't do too many runs cos we talk... alot xDD So yeah. zOMG for one.
And, booty grab. Just because they removed DolphinMania doesn't mean it doesn't exist - and it also doesn't mean you can't be picky with your tanks anymore. I usually only do BG when I'm really desperate though and none of my friends are on zOMG.
Booty Grab gets really boring though ;o; Which is why I don't play it much.
Also, if you have the extra money, gaia cash is really good for gold making. First gen EIs and RIGs usually sell for a bit after a while, and so do the RIG items. First generation EIs especially go for much because they're the first to have all the evolutions available once it's done going through the stages and such.
Hope that helps and good luck with your gold making~ :3