Thanks for your answers, I really appreciate...

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@ squidders
I visited New York 2 times until now and I have seen some things on your list already... I will check those out, which I did not attend, I am sure that will be great...
I may have a Girl with me...

... Hihi... Or I find a nice one there... They say the Girls in the US are fun...
I am very interested in some art exhibitions... last time (some 3 Years ago by now...) I visited nealy every Museum in Town... I will go to the National Museum of History, The Metropolitan, Brooklyn Museum, Guggenheim... I am not sure about the Galleries... And there was a great Museum in New Jersey as well... some...
I would love some more info about Chicago, because I never went there and I am very curious... there will be a broad program from my University (Architectual...), but maybe someone knows something about Clubs, Nighlife and so on...

... For New York as well...
@ mud duck
I think you might mean the MUSEUM OF SCIENCE AND INDUSTRY...?...
http://www.thelocaltourist.com/thingstodo/chicagomuseums.php ...
@ treide
Haha, all right, I will do that... I remember the New York one was good...
@ skeeve
I would like to compare the painting style in New York with the European one... the best would be to attend a Golden Demon, but there is none... I would love to see a good piece in real life while being there... Maybe it is possible somehow...

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I am not a friend of the gaming and stores like Games Workshop in general, I am more interested in meeting people who can paint nicely and talk to them about, well, this and that... this is all...^_^...
The Biggest Book store in the World... A Must...

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I may visit you while I am there, I send you a PM...^_^...
Maybe someone from Chicago can help me out a bit more... I have no clue about the City so far, just some things I know in general and the tipps I got from the Internet, but I am sure there is more interesting stuff (and it is best to be told by someone, some things you cannot read in any guide...

...)...