Western Digital has been making external hard drives for years. The company has a line of drives that are made just to expand the storage capacity on your DVR in the living room.
The latest DVR storage drive is called the My Book AV DVR and it is TiVo compatible with Series 3 and HD DVRs. The drive has 1TB of internal storage and can save 120 hours of HD programs. It can connect via eSATA or USB.
Western Digital also states that it is working with satellite companies and cable providers around the world to integrate support for its expander drives into their DVRs. The drive can also be used to store video from 2010 and later Sony Camcorders. The drive is also compatible with DirecTV and Dish Network DVRs. The device is available for $149.99.