[quote name='hanun1002']Can anyone buy it?
if not, can anyone buy some for me?

[/QUOTE]
It is a rewards program through Gamestop. The program is skewed towards trading in stuff and used items, no surprise there. Nevertheless, you still get points for buying new and used items.
[quote name='"GameStop"']How do I score points?
That's an easy one. Show your PowerUp Rewards card or give us your membership number when you make a purchase at a participating GameStop store, and you'll automatically score points for every $1 spent. This little chart breaks it down:
* 10 points per dollar spent on all new games and consoles
* 20 points per dollar spent on pre-owned games, accessories and consoles
* 20 points per dollar on traded-in games or consoles
* Up to 500 points for activating online, completing your profile and establishing your Game Library[/quote]
There is a free and paid membership.
This is what paid membership for $15 a year buys you.
[quote name='"GameStop"']PowerUp Rewards Pro members get more good stuff. All the benefits of the free program, but with bigger bonuses and other great stuff:
* 250-point Pro enrollment/upgrade/renewal bonus
* Two Epic Reward Giveaway™ entries per purchase or trade*
* Buy 2, Get 1 free welcome certificate** on pre-owned games + accessories in your online account after activation
* 10% point bonus on all purchases
* 10% bonus trade-in credit
* 10% off pre-owned games and accessories
* 10% off new Strategy Guides
* One year of
Game Informer magazine
* Limited to one transaction per day.
** Appears in your Active Offers section under the My Account tab within 3-5 business days after activation[/quote]
Assuming you buy nothing but new items, you need 50,000 points to get a coupon for $50 off any one item at GameStop. Who has $5000 to spend on new items to save $50 from GameStop anyways?
Currently, the $3 PSN codes are available for 4420 points.