Wikipedia
Cramster.com
Cramster (now Chegg Study) provides online homework and textbook help for college and high school students in areas such as math, science, engineering, humanities, business, and writing help. Cramster uses a freemium model, allowing students to pay for or earn access to premium services. Founded in 2002 by Aaron Hawkey, Robert Angarita and Kavé Golabi, the company is headquartered in Pasadena, CA.