Today, while browsing the internet, I got a message saying that Firefox needed to update to ver. 2.0.0.4. That struck me as a little surprising, given that I was already running that version, but I figured that it might be a minor update. I clicked the button to shut Firefox down, acknowledged the various "do you want to close multiple tabs" messages, and then restarted.
Firefox complained that it couldn't update all the files, and that I should close all programs and try starting Firefox again. I closed OpenOffice and restarted Firefox. When I did so, it opened the various windows and tabs I'd had open, along with a new tab noting that Firefox had been updated. However, it also started playing a sound--kind of a neigh or a "baah" from a sheep. When I closed Firefox again the sound stopped, and after starting it back up the sound hasn't recurred.
The whole experience struck me as very strange and suggestive of the presence of some sort of malware, but I don't see any processes that look out of place and matters seem to be running fine. I'm running a virus scan now, but I thought I'd inquire--does this sound like something anyone's heard of before? I'm running Windows XP SP2, fully updated (so far as I know). Thanks for any assistance!
EDIT: The websites I was browsing either don't have sound associated with them (PA and some Legend of the Five Rings-related sites) or do but I'd turned it off (the official Overlord website).
EDIT The Second: Solved. It was the Overlord website after all.