Yeah, I was f20 and bought $20 worth of Cartel Coins (becoming preferred in the process, which has some nice perks) and used it to buy artifacts ^^
Speaking of artifacts, an odd thing happened to me. On Nar Shaddaa (the Imp side), I did a side quest involving an ancient complex that an ancient Sith lord had sealed away 100s of years ago (that should avoid any spoilers, but hopefully those in the know can tell what I mean), protected by an unending legion of droids.
In the Abandoned Warehouse Complex, just before entering the instance, where there's a whole bunch of droids (and a bonus mission to kill I think 40 of them), I got no less than 3 purple drops all within 10 minutes! :O
Was this just outrageous luck, or is this normal for that area? o_O