Estimated Value: $750 million

Last Year’s Rank / Valuation: #32 / $370 million

Business: Online private sales of luxury and fashion brands

Location: New York, New York

CEO: Susan Lyne

Investors: $83M in total financing raised. General Atlantic, Matrix Partners

Analysis: Gilt basically takes excess inventory of luxury goods and sells them on a members-only, by-invitation-only e-commerce site. The company is well-funded and has a management team with a lot of industry experience. We think e-commerce will continue to gain share of the overall U.S. retail market, which bodes well for sites like Gilt.

The company is on track to reach as much as $400 million to $500 million in revenue this year, up from $170 million last year. Applying nearly a 2x revenue multiple (due to low e-commerce margins) brings us to a $750 million valuation.