I found this in another forum –

Cute idea! Here’s a video showing them in action:
http://www.graffitiresearchlab.com/, and here are the instructions for
building them:
http://www.instructables.com/ex/i/7DBB34EAEDFF1028A1FC001143E7E506/?ALLSTEPS

One poster writes –

They can’t be that expensive.. and it looks like a fun thing to do. I bet they would look cool on the Bean — http://www.acclaimimages.com/search_terms/chicago_bean.html But Park Security might not appreciate it after the $14 million they just spent buffing and polishing it. They patrol the park on souped up police Segways.. how futuristic, throwing magnetic leds at the bean and getting chased down by floating cops. I’m sure I can enlist from art students from the art institute near there..