If you want to trade in your old PS2 for some money, you'd better do it soon. According to an advertisement posted on Reddit, GameStop will stop accepting PS2 games, accessories and consoles as of June 1st.
By stopping PS2 trade-ins, GameStop is officially closing the book on the previous console generation. The retailer stop accepting GameCubes and GameCube products a year ago. The original Xbox hasn't been accepted by GameStop since 2009.
Sony officially ceased production of the PS2 worldwide in January. About a month later, Sony announced the PlayStation 4. They're expected to release the console this fall. As GameStop gears up to start selling the PS4 (and the next Xbox), it was inevitable that they'd start clearing out all the remnants of last generation.
If you're in the mood for bargain hunting, you should still be able to buy a PS2 at GameStop past June 1st. GameStop generally sells old games and consoles until they run out of stock. Over 100 million PS2's and 1.5 billion games were sold since the console debuted in 2000, so GameStop has an ample supply of hardware and software for that platform.