Keep in touch: Davy's first college business (though not his first business; he started a Web analytics company the summer before he started high school) was an IT consulting company. As the company grew, Davy found he didn't have the software he needed to keep all of his consultants and the companies they were working with on the same page. He started building what is now EvoApp to use internally. The product, which is being used by more than 200 companies, works through third-party partners to pull all team members' documents, calendar events, and communication activity into one place. Davy, who has four full-time employees, expects revenue of about $500,000 in his first full year of business.