Some people developed the power of being invisible. They start bothering the population and no scientist seems to know how to develop some advanced technology to detect and stop them.
The government announces: Whoever catches an invisible person without killing him will be rewarded with \$1m.
Everybody wants to catch them, so how can they detect and catch them with day-to-day items?
Clarification: Day-to-day items are things that everybody can find at home or at a local store and are not expensive.