One of the most places where they could place advertisements would be when someone is watching a show online.
I was catching up with Grey's Anatomy the other day, and Target was featuring a commercial every 10 minutes.
It was an interesting commercial though, Target used Christina Aguilera to manipulate/attract young consumers to their store. It was a win-win situation for both Target and Christina. She got to feature her new album, while Target used a famous celebrity to appeal to consumers