Claro 3G mobile internet update
I arrived in Nicaragua yesterday, bought a SIM chip from Claro at the airport ($6), put $23 on it (not the $20 that the Claro web site claims), asked the sales gal to use one of their phones to activate one week of internet service, plugged the chip into my Sierra Wireless Compass that I have been using with AT&T in the states and....it works! Even on Linux! (Ubuntu 10.04). $20 for a full week of laptop internet access is great. And the modem costs under $100, either in the states or down here, so why not go for it if you are traveling here?
Don't make the mistake I did, which was: Immediately after buying the chip, I plugged it in and went online. Worked great, but I was paying a crazy per-minute price (something like $1/minute). You need to send a message to activate it for a day ($6), week ($23), or month ($69) before using it.
If you have Windows, you can use their software to send the activation message through the modem itself. Under Linux, you have to plug the chip into a SIM-compatible phone to do it. You can borrow a phone from anyone off the street--since you are using your SIM chip it doesn't cost them anything.
I was able to connect at the airport, and also now in downtown Esteli. According to two online speed tests, I am getting between 1 and 1.5 megabit/second download, and 115 kbps upload here in Esteli.
The only glitch so far is that it seems like the connection was timing out after 1-2 minutes of inactivity. I have set my email client to poll for new messages once per minute, and it hasn't dropped me yet, so fingers crossed.
I will report later on Claro 3G coverage in smaller towns and remote areas, and also on Movistar 3G services (which I haven't yet tried).