If you ever had a need to find out what a particular flight was doing in the VATSIM airspace in the _past_, for example when verifying a post-flight report, then you know very well how complicated it is. Not only you need to collect and parse VATSIM's servinfo feed every couple minutes, but you also need a large database to store it locally. Such a service is also a huge bandwidth waste, because you download 700 pilots every 2 minutes so that you can later extract just one particular person.
vroute is providing a free service for everyone interested, especially VA webmasters - a Time Machine. With the vroute Time Machine, you can look up what a particular flight was doing in the airspace over last 24 hours. It is not intended for end users, who would be certainly more happy with a nice user interface like vataware, but for those who will parse this information with their own software.
The Time Machine can be queried in two ways - by callsign or by PID. Just download the page:
http://data.vroute.net/services/flthist ... ign=CLW216 (for query by callsign)
http://data.vroute.net/services/flthist ... pid=814600 (for query by PID)
and you will get data like:
2008-12-07 20:19:51 814600 CLW216 41.968769 24.042440 450 171 35020 EPGD LGIR
2008-12-07 20:21:51 814600 CLW216 41.727451 24.130550 450 171 35020 EPGD LGIR
2008-12-07 20:23:51 814600 CLW216 41.491169 24.153419 429 194 34989 EPGD LGIR
(tab-separated) where the columns mean timestamp, pid, callsign, latitude, longitude, groundspeed, heading, altitude, filed departure and arrival airports. If the above link gives you empty result set please substitude PID/callsign for someone who is actually flying now or was flying recently. The data is collected for pilots only.
There are no special conditions for using this service, I'm just trying to help others with the data that I anyway collect. If you find an actual use for it, I would appreciate a short email. Please note that additional columns can be added at any time - keep that in mind when writing your own software. If there's something you always wanted to get from VATSIM but it was not in the servinfo file, drop me an email (firstname.lastname@example.org) and I'll see if I can deliver that.
ps. anyone interested in geographically-limited servinfo feed, i.e. something where you can specify lat/lon range and get JUST the planes and ATCs in that area? could be another nice bandwidth saver.