I'm really ticked right now.  Anyone familiar with my "Attack of the Squirrels" parody?  http://www.amiright.com/parody/2000s/avrillavigne208.shtml

Someone made a Nine Days parody about evil squirrels ruling the world also.  Like we both could have thought of that idea.  I wouldn't have minded so much if he just gave me credit for inspiration, but he didn't.  Furthermore, my comments won't show up for some reason.  

Actually...I think you could have both had the idea.  It has happened before...and it will happen again...and there is nothing more wasted than the time you spend worrying about it.

If he/she did get the idea from your parody it would have been nice if he/she had credited you, but chances are that Arwen is right and that you both had the same idea at separate occasions. Furthermore it might not be such an original idea as you think right now when you´re mad, take all those millions of sunday morning cartoons or comic books that exists for example: Evil (insert weekly variation here) tries to take over the world is a standard formula.

After being here for soooooooooooo long I have come upon the SAME issue. So it is likely possible that the other artist thought of the same idea. Ideas are never stolen, sometimes borrowed without permission, but never stolen. If you don't believe me then check my parody of Disturbed's "Stupify". In fact, I had the exact same reaction you had, but in the end it all worked together for good, and I became friends with the one who wrote a duplicate parody of mine, (not plagarized, he used different words, but had the same idea).
Another parody idea that I sometimes have believed to be stolen is the overdone "Bong Song"s. I submitted mine first, and since then I have continued to see more than two more Bong Songs. So I know the frustration, but it's nothing to really get worked over about.

Peace out and keep spoofing,
From S.T.G.

I suppose.  It just seemed too random and unusual a concept.   ???

Here's my own experience with this issue ...

First, I posted a parody of "Kung Fu Fighting" that I called "Junk Food Fighting", and I made sure to put an announcement at the top of my parody that gave full credit to Ethan Mawyer's own parody of the same song (also called "Junk Food Fighting"):

Here's my parody "Junk Food Fighting":  http://www.amiright.com/parody/70s/carldouglas3.shtml

Less than 3 weeks after I posted "Junk Food Fighting", the following parody appeared on Amiright:
http://www.amiright.com/parody/70s/ccarldouglas0.shtml