One of Australia's internet bookmakers has just started a service called MBet. It allows you to access the website and place bets with your mobile phone (provided you have the right mobile phone). Go to
www.sportodds.com.au and look at MBet to have a look.
I don't have the right mobile phone so cannot say how well it works. But this seems like a clever idea and the right way to go if you can pull it off. Many people have mobile phones not many have pocket PCs.
I have seen some discussion on Betfair chat about use of pocket PCs and the Betfair site. General view seems to be that at this stage you really need a laptop computer to use Betfair away from a desktop. But I did hear a whisper about Betfair looking at the mobile phone strategy in the manner of SportOdds.