I was wondering if it is possible to create an XML based ACARS guage for FS2004. Specifically, is there a way to log calculations and other position data and then output that to a website both streaming and in whole at the end of a flight.Thanks!

Sorry, no. XML does not allow such complex functionality...Possibly one could write such an application in C++, but even that would be extremely difficult - if possible at all! - without linking to an application that would run outside the FS loop.

I think the way to go with this would be to add-on an app to the ATC "radar", or perhaps intercept multiplayer data.Not sure how you were planning on having an XML gauge publish to a web site, even if the data were made available to it via a dll, unless you were planning on having that dll do that too.