Here is an emu exploit i found; please note that i am not the one who wrote this and i dont even know if it works or not.
1. Create a macro (type /macro)
/script local function buy (n,q) for i=1,100 do if n==GetMerchantItemInfo(i) then BuyMerchantItem(i,q) end end end buy ("Marvelous Madstone of Immortality",249);
2. Go to shattrath, in lower city, Talk to Griftah. (Location: Shattrath:65,69)
3. Click on your macro few times. (If you have money you will buy em, when you dont have money you will get em for free.)
4. Sell your stack of 249x Marvelous Madstone of Immortality.
It's working on every server I tried.