Harvard need to reassess their admission policies?
I am not going to comment on the utter folly of sending in a bomb threat to delay an exam. Whoever does that should be found and prosecuted.
But, looking at the IT angle, if you are going to use TOR/Guerilla Mail/whatever to cover your tracks (for privacy, not criminal reasons, I hope) in any situation where someone serious i going to look for you and being found out is non-trivially bad, then
* pick a place you have no connection to, such as a coffee shop or a municipal network in a town that you do not visit often;
* check the place for security cameras and don't stay in the view of any;
* clone a new VM with a bridged, not NATted network and a random MAC address;
* do your dirty (the whole enchilada - a new installation of whatever you need for TOR,etc.), with a time delay;
* shred(1) or similar the whole VM;
* sanitize your history and logs on the host.
Preferably, that's after you burn a different MAC address into your network card but before you restore the factory one. Still preferably (maybe), use a throw-away phone (bought for cash in a different town) as an access point and then do throw it into a remote brook (NOT the Charles river - don't do anything near home/work/campus).
How difficult can it be, really? Really - very. Much more difficult than *any* single Harvard exam, I suppose. Having said that, just figuring out the relative difficulty of doing this compared to sitting an exam - and the risk/reward ratios - should be expected, along with that other thing called common sense, of anyone who managed to get into Harvard. Which brings me to the point in the Subject line...