how do i open a *.nat file?

[MrHappyMonkey]

I just downloaded what I thought was an mp3, but it has a .nat file extension. What do I open this with? I tired renaming it to .mp3 but winamp doesn't like it. Any ideas?

 

[vtqanh]

maybe rename it to a .zip and unzip it? I've never seen .nat files

 

[ComputerMonkey]

Might want to do a virus scan on that. I've never seen a .nat file before.