It never fails; you want to upgrade your aging PC, but you still need that archaic RS-232C serial port for controlling your Parallax Boe-Bot, using that serial mouse, getting online via your trusted Hayes ACCURA V.90 modem, and, even, programming your Pfaff 2140 sewing machine. Apple Boot Camp enlistees can run into a similar RS-232C port quagmire using an older Windows app on a MacBook Air.

A: Tagging is the act of assigning your own keywords to things online—photos, blog entries, bookmarks—so that you can easily categorize, locate, and share them in the future. One of the best examples is del.icio.us, which lets you save Web bookmarks to a page on the site instead of to a file stashed away on your computer. This way, you can access them from anywhere and let other people see what sites you like.