The Unicode Home Page can get you up to speed on the international character code for information processing with an overview of Unicode and the Unicode Consortium. It also offers ordering information for the Version 2.0 Standard.
Quick: What's 2498+131277÷6? Don't know? This site gives you the source code for a pocket calculator implemented as a Java applet. The calculator is Sweden's Mikael Bonnier's first Java program, so he's sure to appreciate a little feedback.
If you're interested in tons of information on Microsoft's Virtual Private Networking (VPN) technology, based on the Point-to-Point Tunneling Protocol (PPTP), this is the page for you. A neat, Frames-based page will tell you all about adding secure, low-cost remote access to corporate LANs via the Internet. Also, you can view a copy of the PPTP spec.