A cottage fundraising industry has sprung up around the worst oil spill in U.S. history, with small businesses doing their part to help plug the leak and clean up the mess.

Mallory Whitfield, who blogs about handmade goods and in March opened the online store shopmissmalaprop.com, is donating a yet-to-be-decided percentage of her profits to the Gulf Restoration Network and the Institute for Marine Mammal Studies in Gulfport, Mississippi, where she grew up. 

Her aim was just to help, but Whitfield can't help noting she's doing well by doing good. "It's pretty hard to quantify whether donating to oil spill relief efforts has helped sales," she told Inc.com. "But it has definitely helped with press, which is invaluable to me."

Envicorp Products – an environmental products company based in Houston that opened its doors in September 2009 – is donating 100 percent of its website sales revenue during the month of June to the National Audobon Society. The company's founders – Tana Collins and Stephanie Collins (best friends, but not related) – say even if they weren't Alabama natives with strong ties to the Gulf region, they'd still be helping out because of their strong feelings about the environment.

"We started our business in the South because we hoped to be a catalyst for change in this area," Tana Collins told Inc.com. "Unfortunately, less than a year into our business, the worst man-made environmental disaster has occurred in our backyard."

Envicorp – whose first product is the reusable shopping bag called the "Envitote" – is also using all of its social media networks to promote advocacy and awareness. "We still wish we could do more and that other small business owners would match our efforts," Tana Collins said.

T-shirts are a popular way to spread the word and raise funds. A sampling: Lauren Thom of Fleurty Girl, a collection of New Orleans-inspired t-shirts, designed a special $20 organic cotton "Rescue Me" shirt. All proceeds will go to the Audubon Institute's Louisiana Marine Mammal & Sea Turtle Rescue Program. To avoid using petroleum-based products, the green-turtle-and-oily-splotch design is printed with soy-based inks.

Coast Apparel, a two-year-old South Carolina clothing company, earlier this month launched its own "Save the Gulf!" t-shirt and is donating 100 percent of the proceeds ($5 for each $25 t-shirt sold) to the nonprofit organizations Coalition to Restore Coastal Louisiana and the Gulf Restoration Network (GRN).

"Our business was founded and specifically named for the love of the beach and the surrounding coastal environments," said Coast's COO Chad Odom. "It became my mission to somehow contribute – and give others a way to contribute – in an effort to save the gulf."

And fashion company Defend New Orleans – launched in 2003 – brought back its "Defend the Coast" shirt, originally created for Voodoo Fest. All of the proceeds from sales of the $25 shirts will also go to the Coalition to Restore Coastal Louisiana and GRN.

Entrepreneurs and inventors aren't just using their talents to help raise funds, though. Some are hoping to use their ideas to actually plug the leak or speed the cleanup – and maybe make some money in the process.

BP spokesman Mark Proegler says the company has received more than 80,000 suggestions about how to handle the spill. A team of about 40 people reads the ideas, about 250 of which have made what Proegler calls the "final assessment stage," which includes testing the technology, according to USA Today.

One idea that's made the final cut: A way to separate oil from sand from Houston-based Clean Beach Technologies. Another idea being studied has come from actor Kevin Costner, who's invested $20 million in a product that could purify water and separate it from oil.