The Next Big Ideas: Cool Products from America's Coolest Young Entrepreneurs

ModCloth began by selling vintage clothes sourced from thrift stores and estate sales. The site now primarily sells new, retro-inspired women's clothing, shoes, accessories, and decor from more than 300 designers worldwide, but it still maintains a small section of genuine vintage items. Founders Susan Gregg Koger and Eric Koger have built a loyal following through Twitter and Facebook, and by employing a team of 20-something writers and stylists, who reflect the site's primary demographic.

On Foodzie.com, food lovers can discover everything from specialty olive oil pressed from olives grown in the hills of San Miguel, California to truffle popcorn popped in Southern Pines, North Carolina. Launched in 2008 by former Virginia Tech classmates Emily Olson, Rob LaFave, and Nik Bauman, Foodzie was designed to give small food producers a way to extend their reach beyond their local communities -- a virtual farmers market of sorts. More than 200 artisanal food producers from across the country now sell their goods through Foodzie's online marketplace, offering consumers specialty and hard-to-find items from nearly every food category, including baked goods, cheese, and coffee.

Ascension Aircrafts sells and leases general aviation aircraft -- from four-seat piston-powered airplanes to medium-size corporate jets. In the recession, founder Jamail Larkins has been helping banks resell aircrafts held as distressed assets, in some cases purchasing the planes, refurbishing them in-house, and adding them to Ascension's portfolio to sell or lease to clients.

Justin.TV allows anyone to broadcast live video on the Internet for free. The site attracts 31 million unique users a month -- and hosts live broadcasts for the likes of the Jonas Brothers and Rep. Ron Paul, along with hundreds of thousands of video bloggers, musicians, and would-be reality TV stars.

DANNIJO jewelry is handmade in New York by sisters Jodie and Danielle Snyder. The duo works off of their differing design aesthetics (Danielle has a rock 'n' roll style while Jodie's is more Old Hollywood glam) to inspire their collaborative collections, which incorporate wire work and materials sourced from all over the world. The DANNIJO line now includes four collections, the first of which was sold to Bergdorf Goodman in March 2008. Since then, they have acquired 75 accounts worldwide and lots of buzz in celebrity circles. Natalie Portman and Beyonce Knowles are big fans.

When all the world is a canvas, creativity knows no bounds. That's the inspiration behind IdeaPaint, a paint that turns any flat surface into one big dry-erase board. Launched by Babson College graduates John Goscha, Jeff Avallon, and Morgan Newman, IdeaPaint has garnered a wide range of devotees since it hit the market in 2008 -- from children who are now free doodle on the walls with impunity to NASA scientists whose computations are no longer confined to the constraints of a standard whiteboard. The company is working to bring its paint into retail stores, but is currently sold through a network of distributors and on the IdeaPaint Web site. Cheaper than traditional whiteboards, a kit that will cover 25 square feet costs about $100 and is available in a range of 10 colors.

Apture's platform enables publishers and bloggers to string multiple Web sites together in a single hyperlink. When readers click on an activated link, they can browse other related content, such as a Wikipedia article, a YouTube video, or a Twitter feed, without leaving the main page. Apture's technology can also be used to embed videos and other media within a single window. The company counts The Washington Post and The Wall Street Journal among its clients.

As a self-professed class clown, Hey Josh founder Josh Shipp turned his gift for gab into a business venture. From motivational speeches to "advice kits" that contain CDs, DVDs and workbooks, as well as his own TV show debuting in October, Shipp's special brand of teen counseling has him well on his way to achieving his goal of becoming the "Dr. Phil for teenagers."

City-dwelling guys always want to be in the know, whether it's about new restaurants, bars, or clothing. Thrillist is there to help. Its free, daily e-mail newsletters highlight restaurant openings, bar specials, and apparel launches in 12 major cities, including New York, Chicago, and Los Angeles. With 1 million subscribers, Thrillist is fast becoming a morning ritual for guys, a big boost for companies that earn a mention, and a target-rich environment for advertisers.

Kyle Smitley started Barley & Birch after spending time researching the validity of apparel companies' organic claims. She noticed that in many instances clothes were labeled organic or eco-friendly, but the company's processes and materials didn't support the claim. This was especially true among producers of kids' clothing. So she decided to start her own line that was entirely accountable to both the environment and its customers. Barley & Birch uses 100 percent certified organic cotton, and water-based inks that don't pollute the environment. Profits go toward offsetting emissions, and their manufacturers have been vetted by Green America as environmentally responsible companies.

When Elliott Bisnow needed advice on how to run a business as a young entrepreneur, he started hosting networking trips to learn from others like him. Today, his company hosts two marquee events each year, held in locales like Miami and Aspen, Colorado. Bisnow parlayed the popularity of his events into a roundtable at the White House, which drew rising stars like Zappos CEO Tony Hsieh and Mint.com founder Aaron Patzer.

Hype Machine is a free service that helps members find cool, new music. The site displays the most recent posts from about 1,500 popular music blogs handpicked by staffers from the dozens of submissions sent in every week. Hype Machine’s 1.2 million unique visitors, who visit the site 13 million times a month, can stream music directly from the site with links to purchase the songs from iTunes and Amazon or buy tickets to upcoming shows. Founder Anthony Volodkin incorporated a social networking element by letting users select the blogs, songs, and other users they like, and displaying the most recent songs from their personalized picks on a dashboard that can sync up with their Twitter or Last.fm accounts.

Thirteen-year-old Maddie Bradshaw was looking to decorate her middle-school locker, so she took an old bottle cap, sketched a portrait of Albert Einstein inside, and affixed it with a magnet. The idea soon caught on with friends -- and the rest is history. M3 Girl Designs, which Bradshaw runs with her mother and sister, now sells thousands of Snap Caps, which can be worn as charms on necklaces, bracelets, and hairpins.

Mashable is an influential blog covering the latest social media and technology news. Since June the site, which gets 7.8 million unique visitors and 12 million page views a month, has surpassed the more-established TechCrunch as the most popular tech blog, thanks to founder Pete Cashmore’s ability to appeal to the sudden mainstream interest in leveraging social media. Its coverage combines breaking news with how-to guides for businesses and consumers. The blog has also gotten a significant boost in traffic from popular social networks like Twitter and Facebook. Mashable has more than 1.5 million Twitter followers and is one of the most re-tweeted users on the service.