Grinding Gear Games is opening its Path of Exile beta servers to the public during its Public Stress Test Weekend for free. (You'll be required to create an account and download the game to your computer. It's currently only available for Windows.) That's the best such offer we've seen for this multiplayer online role-playing game, which is still under development. The test weekend lasts from May 11 at 8 pm ET until May 14 at 2:59 am ET.