Every homeowner values his house so much. Who wouldn't? He has invested thousands of dollars into building, furbishing, remodeling, or improving their home. Additionally, home is where the owners keep their valuables, such as, cash, jewelries, bankbooks, important documents, and irreplaceable heirlooms.

Therefore, the loss of any of these items to an intruder is particularly devastating to a homeowner. Within a few minutes, a burglar can sneak into the house and cart away these expensive items.

But burglars are not the only threat. Indeed, the most unexpected threat comes from the inside.

Let's say a homeowner hires a nanny to watch over the baby while he is away. If he is unfortunate enough, he has hired a thieving nanny. With everything in the house virtually accessible, she can steal all that she wants or takes a peek at something that is not supposed to be seen.

Even if she is not a thief, chances are she will lie to clear her name if something goes wrong such as when the microwave oven blows up due to misuse or the TV broken due to an accidental brush.

That is why owners use every measure to ensure the safety of their homes. One of these measures is the installation of security cameras.

Security cameras allow a homeowner to monitor all activities around the camera's location live. If the camera has a recording device, he can view the recorded footages in a later time to gather evidence of any wrongdoing. Here are some of the most unobtrusive cameras that you can buy to provide home security.

1. Air-freshener spy camera – this camera is so small that, as the name implies, it can fit inside an air-freshener dispenser. You can then hang it on a wall, filing cabinet, or any surface. It is very subtle and is perfect for any room.

2. Radio-clock camera – this book-sized camera can record real-time videos or high-definition still shots in an SD card. Recording time and date can also be shown within the picture or video. Aside from being a security system, this device can also act as an alarm clock and a radio, waking you up or lulling you to sleep gradually. You can also tune in to your favorite radio station or play your favorite iPod tunes in it.

3. DVD player camera – this security camera is housed in a functional DVD player. The images that are recorded by the camera can be played directly from the player to the TV; it only needs an RCA cable for the connection. That means, you do not have to buy separate monitors or a software program that can read images. Of course, it can play regular DVDs.

4. Book camera – believe it or not, this camera fits into a housing that is shaped like a book. You can place this between real books in your home library. It contains a high-quality CCD camera that is built inside the book.

Best of all, these cameras cost less than a standard CCTV camera.