AbeBooks - AbeBooks has millions of new & used books, rare books and out of print books.
Kahoot! - Kahoot! makes it easy to create, play and share fun learning games in minutes—for any subject, in any language, on any device.
Chegg - Save $$ on textbooks. Rent, buy or sell your books today and get 24/7 homework help when you need it with Chegg Study and Chegg Tutors.
Sli.do - Slido is the ultimate Q&A and polling platform for live and virtual meetings and events. It offers interactive Q&A, live polls and insights about your audience.
eBay - Buy and sell electronics, cars, fashion apparel, collectibles, sporting goods, digital cameras, baby items, coupons, and everything else on eBay, the world's online marketplace
Mentimeter - a web-based polling tool for workshops, conferences & events