Evernote –  collaborate with shared group notebooks
Google Forms – create interactive forms for surveys and quizzes
Padlet – collaborate with a real-time message board
Penzu – collaborate with shared online journals
Piktochart – create infographics of your content
Prezi – jazz up your presentations (but use with caution)
Poll Everywhere – create quick polls for formative assessment and display real-time responses on your screen
Thinglink – make images and videos interactive by adding mouseovers, links, and other media