Okay, first I want to say this is my first "Exploit" post and I'm kind afraid of getting flamed around here because I'm not 100% sure if this is actually one "Exploit" tough, here it goes ....
I was just now leveling my mining around badlands when I found 2 mithril veins right next to each other, first I used mining in one of them just once! after that I mined the other just once also, yes, I got 2 levels and until here is everything normal, but after mining the 1st vein again I got another mining level and when I got back to the 2nd vein I still got ANOTHER level.
ScreenShot: http://img169.imageshack.us/img169/5783/wowug5.jpg
In other words, mine the vein [A] once = 1Lvl. , mine the vein [B] once = 1Lvl., go back to the vein [A] mine it once again = 1Lvl, go back to vein [B] and mine again and so on ~
I couldn't find this with search so I hope its not a repost :/ If so please delete it :/
Thanks for reading and I hope this becomes useful for any of you