R.S.S. may become an invaluable Web tool, but at the moment there are still a few kinks to work out. To add R.S.S. channels, for example, you have to look at Web sites for orange buttons labeled R.S.S. or XML. After you click on the button, you usually have to cut and paste the address of the feed into the reader software. Some reader programs can grab some feeds automatically, but it’s hit or miss. Furthermore, finding new R.S.S. sources takes time.