Google has plunged its fingers into the online travel pie with the beta launch of a search feature that provides swift access to airline flight information.

Typing in two city names or airport codes into the Google search engine will now bring up a box for flight dates, which will then connect directly to either Expedia, Hotwire or Orbitz travel sites. Clicking one of these options opens a page listing all available flights on the date selected.

As one of the largest sectors in the ecommerce universe, internet companies are keen to increase their footprint in the travel sector. The launch of Google's new flight search tool coincides with a brand new beta offering from Yahoo! called Trip Planner, a community-based online travel guide.

Trip Planner allows users to create and share trip itineraries and travel tips using a combination of search technology, maps, bulletin boards, and local listings. It also exploits the company's recent Flickr acquisition, enabling users to share pictures from a trip.

The planner will also invite users to submit reviews and ratings of destinations, hotels and restaurants and Yahoo! plans to add additional travel-related content to beef up the offering. It is expected to seek a return from the venture through advertising on the site.

Other recent activity in the sector includes the acquisition of travel community site IgoUgo.com by Travelocity's parent Sabre earlier this year. And IAC/InterActiveCorp, the web group owned by Barry Diller, last year acquired hotel review site TripAdvisor.