Your Top 3 "best ways to make gold multiboxing "

[Farleito]

I know this thread is towards multi-boxing techniques, but I find that using auctioneer is the easiest/fastest way to make gold. You can make a ton of gold by flipping items in the AH. I'll grind for some primals on my team, and leave one toon in the AH w/ auctioneer running. You'd be very surprised to see how many people mistype prices. They put X silver instead of X gold... some people put epics up for practically nothing. I've flipped that epic druid staff for 1400 gold a couple of times.

...just thought I'd throw that out there.

[Bradster]

Well here’s my story on making gold.
I think I gave my guys all neatherweave bags to start, along with 20G or so I think each. After that at level 6 or 10 I bought them wands, after that I never bought a piece of gear for them since, ever! I used auctioneer, like some suggested it’s a great tool and takes all the work out of figuring out the best price.
At 60 I was able to purchase 5 Epic mounts, couldn’t afford all the training at 60, a very short time in the outlands I could however.
I’m level 69 now. I think I’m 400-600G away from having 5 flying mounts. I’m only 3-4 bars in to level, which running instances normally net 200-300G a run for just leveling. So I should be in good shape at 70 with a little left over.
From there I will have to do the daily guide and see how that works out. Would like 5 Drakes if I can handle the grind between Battle grounds (I intend to grind BG’s for all my gear)

[BobGnarly]

I will third (or greater) the AH angle. I've made a ton of money there at certain times in the past, and it's very easy to do. You aren't running around, just playing the market.

My problem is that I don't like being tied to it, so I just play it when I get a chance. If you have the time inclination to play it consistently, like 2-3 times a day every day, you can corner small markets and really reap the cash.

Example: Back around the release of sunwell, there was this crazy fluctuation of prices on Large Prismatic Shards. I had a way to make LPSs all day long from mats in the AH, and enough money to buy any reasonably priced mats in addition to any undercut LPSs on the market. For about a week and a half, I owned the market on LPSs and made TONS of money. Eventually, as is always the case, enough people realized the potential and started to play so I got out, but it was great while it lasted. That's the key here, just like investing RL. You have to know when you've ridden the train to its end and get off. Don't hang on because of how great it was and ride yourself into a loss, just be happy for the opportunity you did have a recognize when it's time to get out. People will say "but I quit too soon," and sometimes you will, but I like Warren Buffet's reponse to this: "I've made a lot of money selling too soon" (look him up if you don't know who he is).