Seeing as this is American Independence Day, some of you might want to celebrate no longer living under the protection of a divine monarch, perhaps by playing a video game. A PC demo's out for Airtight's Quantum Conundrum now, so why not see what the new first-person puzzler from Portal co-creator Kim Swift is about before you munch down on your hotdogs and whatnot.

The demo's a 662MB download through Steam. The demo's rather short, a custom-made section showing off several of the different dimensions and how their reality-changing aspects interact. It only took me about 15 minutes to complete, but hey, it is only a demo.

Quantum Conundrum launched for PC in June at $15, and hits Xbox 360 and PS3 next week.