Sick of standing in line at the post office? Try going online to the post office instead. At the USPS's Web site, you'll find dozens of time- and money-saving services. Click on the ZIP codes icon from the home page and you can look up ZIP codes for addresses nationwide. Or keep tabs on packages by using the site's Express Mail tracking feature. There's also a "rate calculator" that helps you find the most cost-effective method of mailing letters and packages. Just enter the article's weight and ZIP codes of the origin and destination, and up pops the price for shipping it by various methods.