Hey Guys, I just released an update to my free, open source Data Logger: Nimbits v3.0.9 for all to you. If you haven't seen my previous posts about it, Nimbits is a cloud based data logging server you can feed arduino (or any other) data into. You can use the public instance i host here: http://www.nimbits.com
and/or download a copy and install on app engine or your local environment. You can feed data right from an ethernet connected arduino right out to the cloud without a server in between, i show how to do that here: http://nimbits.blogspot.com/2010/11/data-in-connect-arduino-to-cloud.html
You just set up data points and feed data into that channel. It does alarms, calculations and has a REST API interface to program against, relays to facebook and twitter etc.
Check it out, let me know if you have any questions.