unusually high dial up speed

[woodturner46]

ok, this isn't really a problem, but i didn't know where else to post it.
i have an ancient dial up connection, on a good day i can usually download any file at around 3kb/s that seems normal and i am happy with that, except earlier today, to my extream astonishment, i was downloading an .avi movie file and it started out just fine at 3kb then it went to 5 then to 7 and keep climbing until, no joke, it reached 29kb/s i couldn't believe what i was seeing i checked my connection speed and it was at 33060k (on a 56k modem) is there any explanation for this? is there any way to get it to do that again? i consider myself somewhat computer literate but this has got me stumpted. any suggestions would be nice.
justin