Online rental marketplace Rentcycle on Monday secured $300,000 of a slated $1.4 million funding round, according to an SEC filing. (The company was named winning startup at Vator Splash SF in Febuary 2010.) Listed on the filing is Craig Shapiro, CEO and founder of Collaborative Fund.

It appears that this would be the Rentcycle’s first round of institutional funding, though I’ve reached out to founder and CEO Tim Hyer to confirm.

From sporting goods to apparel to wedding necessities, Rentcycle seeks to be a one-stop shop for all your rental needs. Though one (like myself) might be inclined to imagine Rentcycle fitting squarely in our Web 2.0-saturated world, providing a platform for anybody to rent out anything to anyone, one would be mistaken.

The only entities that can list on Rentcycle are vendors that actually serve as rental businesses. In San Francisco, for example, there’s Big Swingin’ Cycles for bicycle rentals, Gocar Rentals for those goofy-looking go kart tours and SF Party for... cotton candy machine rentals.

It’s a really novel idea, in spite of its simplicity and obviousness. And Rentcycle executes the idea with elegance and acumen.

The service is currently available in 48 U.S. cities.

Rentcycle is one of a large and growing body of lean, bootstrapped startups building out a Web service with limited costs. In a blog post from last October, Kevin Halter, co-founder and VP of Sales at Rentcycle, reveals the many ways the company saves money: no office space, free collaboration tools, free software and Web hosting, home-grown public relations and more.

Interestingly, the five-strong team is “actively hiring” four developers, quite an expensive task for a bootstrapped startup. This is likely at least one part of the company’s decision to finally turn to institutional funding.

To peer into the roots of Rentcycle, check out this episode of Startup Sessions from early last year.