Just out of curiosity:
Is there any real world application written in INTERCAL?
TIA ;)
It depends on what you mean by "real world applications".
If you're talking about code that's been packaged up into a piece of software and sold to the masses (something like a smartphone app or a videogame) I don't know of any and strongly suspect none exists. INTERCAL is too ahead of its time for most modern programming applications.
However, there are a surprising variety of things which have been done in INTERCAL.
There are any number of practical mathematics programs that have been programmed in INTERCAL. I myself have written several. That's not to say that people haven't written better versions of these algorithms in other languages, but it's perfectly possible to write them in INTERCAL and people have done it.
If you want proof that INTERCAL can be used for Serious Computer Business, you might consider the INTERCAL quine, found here. While quines don't really do anything, per say, they are a real thing that real people try to do with real programming languages - and so could be taken as "real world", in a sense.
Perhaps the pièce de résistance of INTERCAL glory is the CGI script which takes INTERCAL out into the wide world of the internet. If you're interested, you can read all about that one here. I think that's about as real world as it gets for INTERCAL.
If you want to further explore, http://www.muppetlabs.com/~breadbox/intercal/ is a good starting point for finding just about everything that has been done with the language.