We love free things, and we like them even more when they're awesome. Those two don't go hand-in-hand nearly enough, but for a short while, they both apply to Portal, a single-player first person puzzle platformer that was born out of Valve's Orange Box bundle and quickly gained notoriety as a hella-fun standalone title.
From now until September 20, 2011, you can download Portal from Steam absolutely free, no strings attached. Grab it by then and you'll discover why it was such a popular title, assuming you don't already own it. The limited-time giveaway is Valve's way of bringing attention to its Learn with Portals initiative.
"When we heard the buzz surrounding the new role video games are playing in education, we had to throw our hat in the ring. Today, innovative educators are finding ways to incorporate Portal and Portal 2 into their classrooms—helping teach physics and critical-thinking skills. It’s eye-opening to see how video games can be used in amazing and unexpected ways to help educate our next generation," Valve states on its new Learn with Portals website.