Just a comment. I used to travel with my Airport Express, but many hotel wired Ethernet connections require some kind of login page before they will assign you an address and let you connect to the internet, making it less likely that an Airport express or other router will be useful.
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This is just not correct, and I am surprised to be the first to comment on it. I am in a hotel almost 300 days per year, and use my Airport Express is ALL of the rooms that have wired internet. I'll mention the process and the benefits below:
1. On the Top of the airport Express (the panel with the ports etc). There is a reset button. Plug the ethernet cable into the Airport Express, then plug the airport express into the electrical plug socket.
2. Take the closest pen (on the table with the little pad that 99.9999% of the hotels in this world provide you), and stick it into the little indent that is the reset button on the airport express. Hold it down until the light flashes fast (about 5 seconds). That resets the airport express. This seems to be essential to get most hotels to pick it up, and connect properly
3. Now, wait about 90-120 seconds (This wait time is crucial, nothing will show up on your device immediately). This is how long it usually takes for the airport express to show up on the wireless network list on your device (macbook, ipad etc).
4. When it shows in your network list, it will show up as Apple Network followed by some numbers and letters.
5. At this point, if you select Apple Network ff9f9f9 (or whatever yours shows as) as your wireless network, it will take you to the login page for the hotel network. Login, and off you go
The other GREAT benefit to this over the wireless network in the hotel is that you can connect multiple devices in your room to the same apple network f9f9f9 etc for the price of one connection, or free if they don't charge. For some reason iphones don't seem to stay connected for very long to hotel networks, but it seems to have no trouble staying connected to the airport express, so this is another benefit. The other nice thing is that if you use apps like "Things" you can sync etc over the existing network a lot easier
Hope that helps
J