Bostino (Sept. 18) -- CS alumnus Max Levchin is perhaps best known as a co-founder and the former CTO of PayPal, as well as the founder of photo sharing/collaborative presentation platform, Slide. But he’s also had his hand in other notable ventures like Yelp, Yahoo! and Evernote. More recently, he has ventured from Silicon Valley to generate a buzz about the annual Levchin Prize for Real-World Cryptography.