I would have thought this was cool when I was 10 years old.
I can't say anything about this site in particular, but be wary of these prank websites in general. A friend of mine sent me a prank call through one and I've received a bunch of sales calls since then. I didn't get any (zero) before he pranked me.
this app is pretty tight. basically you can have it prank call any of your friends and it makes it seem like it came from your #...i wonder what tools he used to build it.
Yes, <insert original submitter> is <insert positive adverb>.