SpeakPipe is a site that "allows your visitors to leave voice messages right from a browser". SpeakPipe make it easy for your audience to reach out to you. They can use the mic on their computer or their iPhone, iPad or Android Phone
Sign up for SpeakPipe here http://basicblogtips.com/uses/speakpipe
Clipping is a handy way to collect important slides you want to go back to later.