Joshua Zimmerman isn't a full-time inventor, but that's about to change. The 30-year-old middle school science teacher has raised almost $100,000 on Kickstarter project, the "Folding USB Solar Cell." With 15 days left, the Milwaukee history buff has well surpassed his $5,000 goal to build an inexpensive, easy-to-use, practical, every-day solar USB system.