Once as free as the air we breathe, most Web-based e-mail accounts now come with all kinds of strings attached. In most cases, these "free" sites either charge for certain services or impose strict limitations in an effort to make you pay for "premium" e-mail packages.

Hotmail, for example, which boasts more than 110 million users, now pushes you to pony up $20 per year or makes you deal with storage-space limitations. While it recently changed its look for the first time since 1996, Yahoo Mail now charges for one of its most useful and heretofore free features: the ability to grab your mail not only from a browser, but also from a desktop e-mail program, such as Outlook or Eudora.

Given these limitations, we must ask: Are these so-called free e-mailers worth the hassle? To find out, we took another look at four top services: AOL Mail, Microsoft Hotmail, Mail.com E-mail, and Yahoo Mail. We set up accounts, monitored the amount of spam we received, and tested each service's security provisions. The result: a longtime champ remains at the top, but a former fave ends up in the doghouse. Read on.