Pop superstar Katy Perry continued to expand outside of the music world this week when she agreed to invest in and become the promotional face of Popchips.  According to a press release, Perry tried the chips and loved them, so she began Tweeting about them, which caught the attention of the brand's owners.  The company approached her about doing some ads, which will begin airing this fall, and she also decided to sign on as a creative partner.  Perry has also invested in the brand, joining fellow celebrity investors P Diddy, Ashton Kutcher and David Ortiz.