Well, I'm having fun with FlightExplorer, and a feature I like is the Flight List that you can sort by whatever you want. I sort by speed, and the fastest registred plane currently is:
AAL1751, A3B6, 824knots at FL290, not updated since 8:57pm EST (ETA 11:19).
I just cross checked on AA.com
and it says the same.
Is it a false reading or... ??