As the nation's fourth largest carrier, T-Mobile tries to one-up its competitors by being innovative and cheap.

Here's another example of that spirit: T-Mobile has a new add-on service called HotSpot @ Home, which allows your mobile phone to serve as your home phone.

HotSpot works with a special router that puts your calls through via an Internet connection. The call quality is nearly perfect. The cost? A mere $10/month add-on to your T-Mobile service – probably much less than you're still paying for a landline.

A whopping 97% of people who signed up for HotSpot went on to disconnect their landline and drop their monopoly local phone companies. That's very telling about how effective HotSpot can be. Another fringe benefit is that you no longer have any need for 2 phone numbers!

But beware, there's a serious danger if you disconnect your landline: You'll save hundreds of dollars every year! There's almost no reason left to have a home phone from a monopoly local company in today's world. Clark thinks about his 19 year old who certainly won't ever have a landline in her life.

Finally, Clark's Internet access glossary is now live.