Music Theory for Musicians and Normal People Toby W. Rush's "Music Theory for Musicians and Normal People" covers a massive range of topics like pitch, rhythm, scales, intervals, and harmonics. The online book itself is arranged as a collection of about 50 PDFs that offer diagrams, notes, and tips for everything music theory related. [more inside]
Free online graph paper generators: variations of squares, triangle, rhombus, and hexagonal, circular and polar, for drawing, gaming, writing, note-taking and much more. Blank Sheet Music (Flash) for all arrangements (PDF). Create and edit your own grids, probability and logarithmic graphs, petri-dish inserts and storyboards. Also, multilingual monthly and yearly calendars. Plus, more than you ever wanted to know about ISO paper dimensions and printable paper models of polyhedra. Prev-ious-ly.
Sciweavers' free online productivity tools include an international virtual keyboard, OCR, image format conversion, and just about every manner of PDF manipulation imaginable.
Alex Cox, director of Repo Man and Sid and Nancy, and one-time presenter of Moviedrome, which was a cult movie education for an entire generation of British people, has posted a ton of free stuff on his site: 10000 ways to die (pdf) - his book on Spaghetti Westerns, the Moviedrome guide parts 1 and 2 (pdf), a video defence of Walker (quicktime), and much much more.
The New Liberal Arts book is out. 47 pages of free pdf about things the various authors think will help prepare you for modern life. Earlier discussion about the planning phase of the book.
Twenty hard-boiled pulp stories from a revived Black Mask Magazine. (Unfortunately, stories are mostly in PDF form.)
PDF-Mags.com. "Free PDF mag's from all over the world with main focus on art, design, illustration and life."
A Technical History of Apple's Operating Systems – Amit Singh posts a free, 140-page PDF "bonus chapter" to his Mac OS X Internals: A Systems Approach.