Two Mad Geeks

This site has a wide variety of PDFs on computer related topics. Some of the topics include: Computer Programming, Cryptography, Security, Networking, Engineering, UNIX/Linux.

Link: Communications Research Group

No matter how meticulously you remove cookies and cleanse spyware and adware from your PC, snoops can still track your movements on the Web. The telltale sign is your IP address. Using free utilities such as Tor, and Provoxy will help render you untraceable.

Link: PC World