Blizzard released information today stating that stacks of gold for sale on the real money auction house (RMAH) are going from 10,000,000 to 50,000,000. Seeing as how a stack of 10,000,000 gold generally sells for about $0.25 USD, and you have to spend a minimum of $1.00 per transaction, this means that you had to purchase 40,000,000 gold at a time for about $1.00 minimum.
After the scheduled maintenance on July 30th, 2013, all new auctions for gold will be stacks of 50,000,000 and will likely sell for the usual $0.25. Since you will still have to spend a minimum of $1.00 per transaction, this means you're going to be able to pick up 200,000,000 gold for about $1.00 USD! This means $10.00 gets you 2,000,000,000 - that's two BILLION gold.
This change will probably be a good thing for new players - people who have little to no gear, as much low end gear is difficult to sell lately and the prices are rock bottom. This also puts a lot of cash into the hands of players who want to use their demonic essences to craft their bind on account (BoA) items. By the same token if you don't already have 100K+ DPS, and unless you're playing hardcore or strictly self found only you have little excuse to be under 100K at this point, you should be able to spend $1.00 and easily break that 100K DPS barrier. With a little research on YouTube and a bit of patience on the auction house you'll be able to easily farm MP5 for demonic essences.
Check out the video to learn more - and see the video description on YouTube for a link to the post Blizzard made on the Diablo 3 forums.