randomizing position of a gl.videoplane

I'm trying to randomize the position of my videoplane in my jit window, but I'm trying to do it in a way that's interesting, organic, something that doesn't just look like it's obviously random... which is basically what my attemps looks like now...

what I'm doing is rendering a videoplane that's beeing fed various pictures taken in real time, and without erasing itself so that my screen just fills up with images continuously. the positions at wich the plane pops up every time has to be automated in some way, unpredictable yet still somehow harmonius, and that where i'm stuck. Algorithms are not my big strength, so I'm never quite sure how to go about creating them, I'm thinking maybe if I ask the community I'll get some ideas to get me started in the right direction...

I've attached my very basic attempt (basically I did this as a placeholder to be hable to test the rest of the patch)

cheers!