This open source textbook by Raleigh, N.C., math teacher Kenny Felder was part of the review of the first 16 digital texts submitted to California's review program as part of the free open-source digital textbook initiative by California's Governor Schwarzenegger. This textbook scored a 96 and met 26 of 27 standards. Felder teaches at Raleigh Charter High school.
Librariies and non profits having book sales can use this site to list their sale for free. It is in beta testing now, but looks like it might have some cool features if you manage book sales. If you try this and review it, let me know, I'd love to know what you think.
This online gradebook, state-standards alignment, curriculum mapping, formative assessment and learning management is free for teachers. If you don't have an online system or are looking for new ones, you may want to check this out.