Google's testing a TV search service in conjunction with Dish Network, allowing users to search content from Dish and other sources such as YouTube.

It would also allow Google to target ads at individual households through a link with its ad-brokering business Google TV, says the Wall Street Journal.

Based on a set-top box, the service is almost certainly based on Android - possibly a cut-down version - and allows users to search via queries typed on a keyboard rather than using a remote control. Viewers could create a personalised line-up of shows.

But it doesn't look likely to hit the mainstream any time soon, as it's apparently only a very small-scale test with a small number of Google employees. The company says it could be discontinued any time.

But cable network Dish currently has 14 million subscribers, giving Google a nice start if it decides to take the service further. Google's TV Ads is already a Dish partner.

It would face some pretty stiff competition, though, as most set-top boxes in the US are supplied by carriers. An online video search engine apready exists in the form of Clicker, which has deals with set-top box manufacturers Boxee and Popbox, and Apple's also been trying to break into the market with Apple TV.