A PDF version of "Structure and Interpretation of Computer Programs" (SICP) by Abelson, Sussman, and Sussman.  Low resolution bitmap images are replaced by vector graphics (SVG) and mathematics is typeset in TeX.  Typography and layout are improved for better on-screen legibility.  This edition is suitable for medium-sized screens (like 10" tablets).

It is based on Neil Van Dyke's Texinfo version: http://www.neilvandyke.org/sicp-texi/

Official SICP page with HTML version: http://mitpress.mit.edu/sicp/

An adaptation to pocket format is now finished: http://github.com/sarabander/sicp-pocket/