If you are travelling to HHC2009 from outside the US, and if you are not a US citizen and you do not have a US visa, then you are either planning to enter on a Visa Waiver or you need to get a visa pronto!
If you are planning to come in from a country that has a Visa Waiver arrangement with the US, then you must register online before you travel. This is a new requirement from the beginning of 2009, so you may not know of it, and so I am posting the information here, with apologies to everyone else.
The scheme is called "Electronic System for Travel Authorisation (ESTA)". Look it up on the web and be sure to fill it in at least 72 hours before you travel.
I have just had it pointed out to me that the official US web site is free at https://esta.cbp.dhs.gov and that others might charge for the same service.
Thanks, normal service is now resumed,
Wlodek
Edited: 17 Sept 2009, 10:34 p.m.