An curved arrow pointing right. Many hand gestures in the US are pretty universal. The peace sign, thumbs up, and "devil horns" aren't likely to earn you any strange looks in the States ...

[B. Aswinth Raj] wanted to control a VLC player with hand gestures. He turned to two common ultrasonic sensors and Python to do the job. There is also, of course, an Arduino. You can see a video ...

Even if you're not big into politics, you've probably seen it by now - the gesture. In a kind of loose ... they extend the closed hand out toward the crowd, as if handing over a sum of money.