The great Greek playwright Aeschylus wrote, “From a small seed a mighty trunk may grow.” True story, Aeschylus. So what happens when the seed itself is massive? Virool, the San Francisco-based developer of a social video advertising platform, is about to find out. The Y Combinator graduate has closed a massive seed-stage financing of $6.62 million from VC super-investors including Draper Fisher Jurvetson, Menlo Ventures, Thomvest Ventures, DominateFund, FundersClub, 500 Startups, Phenomen Ventures, TMT Investments, and a host of faithful angels. According to a press release, the company will use the funds to expand adoption of its platform, which helps advertisers reach their target audiences with promotional videos inside Facebook games, mobile apps, blogs and websites.