One business hasn't been affected by the poor economy: a textbook-renting Web site that does a little bit for the environment after each transaction.

Chegg.com is an online bookstore that lets students rent textbooks for a semester and then ship them back once the term is over -- a Netflix for textbooks, according to the Web site. For every textbook rented or purchased, company owners plant one tree.

"Textbook rentals have been around for a few years, but I think with college tuitions continuing to climb and higher unemployment rates, parents and students are looking for any and all ways to cut costs," company spokeswoman Tina Couch said.

But local stores are not worried about the eco-friendly textbook site.

Ben Lambert, manager of Got Used Student Bookstore, 206 E. College Ave., said the customer service quality is not the same when you shop online as compared to when students come into the store.

"We get all our information directly from the university," he said. "We know what the students need."

Started by two friends, Aayush Phumbhra and Osman Rashid, Chegg.com has been used by students at more than 6,400 universities -- Penn State among them -- and has planted more than 3,000 acres of trees in 21 countries. Phumbhra, who graduated from Iowa State University with a degree in marketing and accounting, wanted to help college students save money on textbooks.

"Moving here from India, the exchange rate made textbooks really expensive for me," Phumbhra said. "It's why I wanted to start a company like Chegg.com to help students like me save money on something that is a painful thing to do."

And many bookstores won't even buy

books back at the end of the semester, he said. This is what he said makes Chegg.com so different.

"We take back your books no matter what, free of cost," he said. "Even if there is a new edition coming out, we still take the old one."

Phumbhra added if students happen to have old textbooks lying around they couldn't sell back to the bookstore, Chegg.com will buy it.

"We'll buy your textbook back from you even if you bought it from another store and give you top dollar for it," he said.

Christopher Agostini, Class of 2009, started using Chegg.com when he was at Penn State after his grandmother stumbled upon the site.

"I thought it was too good to be true, but they did everything perfect," he said. "The books always showed up when they said they would and they always had the books I needed for my classes."