As far as I know, you can't play polo over the Internet. Polo - perhaps some system where you ride around in a horse with a PDA which controls the ball via wireless communications. Better look, better feel, and feature-packed. The nice thing is, if Excite is down, you can log in with the same alias over at Netcenter. If you haven't played before, you'll have to get used to some annoyances.
Many players wish to play extremely short timed games.
It's not always easy to find traditionalists on the system. Then again, you can arrange to play a personal friend over the 'net, and that way, you know what you're getting. The gaming offerings at MSN might be worth a look, as well. Kasparov prevailed, but also accused the World team of taking secret direction from an anonymous chess grandmaster. Aside from chess, there are so many other cool games available through the major portals that they deserve separate treatment.