Inc again has released its list of the 5,000 fastest growing independent companies in the country. While it’s full of the usual suspects, like technology, health, land development and oil industries, green careers are well-represented. In fact, the No. 1 fastest growing company by gross dollars of growth was CH2M Hill, a company managing Masdar City, the world’s first zero-carbon, zero-waste city located in Abu Dhabi.

Even if green careers don’t interest you, the list is an interesting look at what people are buying, even in bad economic times, and what that might say about us. Broken down by category, here’s a glimpse of some of the fastest growing green businesses underway—multimillion-dollar companies, all.

Disasters like hurricanes have kept a number of those thriving in the “environmental services” category in business. They include Ahura Scientific, which designs and sells products for chemical identification and disaster-recovery specialists Alamo1. EnviroWaste Service Group, which provides underground waste management, saw business pick up in hurricane-stricken areas. Others doing well include environmental consultants, businesses that help others comply with environmental regulations, recycling and waste management services, and those who install and distribute synthetic turf in dry areas. No. 2 in this category was Tahoe City-based Integrated Environmental Restoration Services, which restores environmentally disturbed areas in the Lake Tahoe basin. That company’s revenue grew from $338,466 in 2004 to $3.1 million by 2007.

Eco-Products, which makes compost-ready supplies for restaurants, was No. 17 in the food and beverage category. Others include organic tea businesses Honest Tea and Numi Organic Tea, the organic Peanut Butter and Co., Endangered Species Chocolate, organic Late July Snacks and Stirrings, maker of all-natural cocktail mixers.

In the “energy” category, it’s not surprising to find several designers, manufacturers and installers of solar energy systems, many of which were in the top 100 of all 5,000 businesses. Topping the energy category (and No. 7 overall) was Greenline Industries, which makes biodiesel production equipment. Its revenue grew from $318,000 in 2004 to $35.1 million in 2007—that’s a growth of roughly 11,000 percent—with only 20 employees.

Other green ideas that have proven profitable are Dogswell‘s natural pet foods and treats; electric golf carts by JH Global Services; the car-sharing company Zipcar; Baby Earth’s online, eco-friendly baby products; eco-shoes by Planet Shoes and bamboo products from Higuera Hardwoods.