About your sentence that begins "The laptop doesn't really have anything THAT illegal..." Being legal or not isn't exactly like being pregnant or not, because pregnant is a state that is related to the physical condition of the person, but legality is related to the geographical location or to the citizenship status of the person. That said, there is an old saying that there is no such thing as a little bit pregnant. If you think that there is anything on your hard drive that is illegal in any place where you are traveling to, or your flight might divert to in an in-flight emergency, the smart thing to do is to scrub it off your hard drive and use a tool to wipe the empty space on your drive to United States Department of Defense standard DoD 5220.22M -- and do all that BEFORE you travel.

If you have something that is perfectly legal where you are, but illegal where you are going, you have not broken the law where you are going if you don't take the illegal thing with you. If you do take it, and you DON'T get away with crossing with it, the very best you can hope for is that you won't be jailed. Instead, you can expect to have your computer seized and destroyed, yourself deported and legally barred from ever returning to that country. Oh, and kiss your airfare goodbye, too. Or, all those unpleasant things could happen to you AFTER you spend a period of time in jail.

Not sure whether something really is illegal in the US, best advice is to ask a US lawyer. Second best is to ask a lawyer in your country who is knowledgeable in US law. Third best might be the US Consulate in your country. You can always ask HN, but in that case you get what you get and most of us are not lawyers.

Good luck in your travels, have a great time at the math program, and try real hard not to wind up in Gitmo.