
Things to FORGET when you travel include: any sharp objects in hand luggage including nail clippers, scissors, penknives, along with lighters, lighter fuel and firearms (god forbid).
If you are booking a flight which transits in the US, remember to leave yourself plenty of time to pass through immigration - particularly in Miami. See LAGS page for information on carrying liquids in hand luggage.
If you are leaving through main UK airports, remember the ONE piece of hand luggage rule. Although you can, once again, take more than one piece of hand luggage through security at most airports, airlines are becoming more and more strict about letting passengers onto the aircraft with too much additional 'baggage'. So if you don't need it with you, check it in ....or leave it at home.
Other items you are best advised NOT to pack in other luggage are: firearms, meat, any meat products, seeds, fruit, plants and illegal drugs.
Duty free allowances vary and change, but as a general rule goods which are worth more than $400 (US citizens) or $100 (foreign travellers), are your limit.
Visitors, over 21, are allowed 200 cigarettes, 3lbs of tobacco (although where you would smoke is a tricky one) and 34 fl oz of alcohol. The fl oz and lbs, by the way, as well as inches, feet, ounces and yards are worth learning or remembering (dependent on your age); the US operates on the imperial system not metric.
To stay up-todate on the do's and don'ts, the what to do and what not to do, including travel advice, passport and visa information, contact either the US Embassy in London at
http://london.usembassy.gov/ or the FCO (brilliant site), go to
http://www.fco.gov.uk then the travel advice button (near the top left of their site). See also page on Visa Flight Information USA.