Yeah any station game cards you use during the time limit will net you 3X as many points as well. You can get those at retailers like Gamestop/7eleven.
I think 3X is the highest they have for promotions when they have them every so often.
Though, I don't believe you can pay for your subscription with most of their titles any more via station cash, which is disappointing.
This is good if you want to stock up as SOE is going towards free to play. Titles are now going to be supported by micro transactions via station cash. As an example,
Planetside 2, which is releasing soon (Nov. 20th).
>>> here is some more official info on when it, and when it ends.
We would like to wish you a very Happy Halloween with one day of Triple Station Cash!
On November 4th, 2012 SOE is treating you to Triple Station Cash!* Buy Station Cash® in-game, online, or redeem an SOE pre-paid game card for Station Cash® to get TRIPLE!
* Offer is valid between 12:01 AM PDT 11/4/12 and 11:59 PM PST 11/4/12. Excludes purchases of Station Cash by SMS payment.