Today, while messing around on my alt, I came across something interesting. I was buying honor rewards (however I tried it with WG MoH, Badges and it worked) and saw that when I bought a trinket but sold it back to the vendor, it still counted it for credit for Achievement "epic".
I kept buying and giving back, but for different item slots, and the trend continued. I did the same with badges and honor. With 50k honor and 40 Valor badges I would have had two points of credit. However I got it all with just that much.
Also, for trinkets buy one, give it back, and buy a DIFFERENT one and equip it in a different slot. I believe this will work with Arena points also. It is pointless for most people, as this achievement is cake, but its fun for the alts and for the newly granted 80s.
Have fun...