Vodafone recently launched its "Access Gateway" product, which is a plug-in box called a femtocell. This morning, Pocket-lint was invited to a demonstration of one in action from a company called Airvana that makes the devices.

But you might be a bit confused about what a femtocell is, what it does, and why you might want one, so in this edition of "five things", Pocket-lint swings to the rescue with a handy guide.

What the hell are they?

A femtocell is, in essence, a small phone network in your house. It plugs into your home broadband connection and sends its voice and text data through that.

For the more technical among you, you'll want to know that it provides a 3G signal at up to 7.2Mbps. Because that signal's only being shared with the handsets in your house, you might actually have a chance of reaching those speeds, unlike in the real world.

What does a femtocell do?

Well, for starters it should be able to give you a full five bars of reception anywhere in your home. The unit has a range similar to that of a Wi-Fi router, as it has considerably less power than a regular phone antenna.

But it can do more than that too. It monitors any numbers on it, and has the capability to interact with handsets, as well as any other devices on your home network.

What can I use it for?

The possibilities are endless, and an API is due at the end of the year, so any developers will be able to use the platform to build upon.

One idea showcased to us include SMS alerts to know when your partner gets home from work, an alert if someone you don't want around (a daughter's boyfriend?) is around, or even an alert if the number of people in your house gets too high (party!).

You could even use it to automatically download photos off your handset when you walk in the door, or synch an address book, music collection or even print documents out.

How much does it cost?

Right now, the only UK operator offering a Femtocell is Vodafone, with its "Access Gateway". That costs £160 for new customers, or an upgrade will get you it with a small stipend on your monthly bill.

When can I get one if I'm not on Vodafone?

Depending on how well it goes, other operators might start offering the unit too. However, each will likely be locked to its respective operator, so all your family will need to be on the same network. An unlocked version might become available in due course, and shouldn't cost much more than £200.

If you have any other questions about femtocells, drop them in the comments and we'll do our best to come up with an answer.