Ironically, "TheTruth101", what you've written is totally incorrect. Merchandise means "anything that can be bought or sold." Buying a computer abroad is "merchandise" even if you buy it for personal use, and in theory you're supposed to declare that. In practice, almost no one does this. I've flown probably 50 times trans-Atlantic and I've never been stopped at customs in either direction, nor have I ever even heard an anecdote of a friend or family member who was stopped at customs for anything other than food-related items, nor have I even seen anyone ever stopped and pulled out of the "nothing to declare" walkway for a random spot check.
You can look up the rules for Switzerland for instance here (in English). Most of EU will be nearly, or maybe even exactly, the same:
https://www.ezv.admin.ch/ezv/en/hom...-free-limit/importation-into-switzerland.html
In any case, if you don't declare, if somehow the stars align and you lose the lottery and get struck by lightning while a meteor hits you and customs decides to randomly check you (probably similar likelihood, though depends on your country), worst case is you have to pay the VAT you'd have to pay anyway if you declared, plus a small penalty, since it's not like you're smuggling a suitcase full of cheap iPads.
The only thing I've ever even heard anecdotes of people getting stopped and fined for is groceries at the Swiss–French and Swiss–German border, in cars. I've never heard of anyone I knew, or even a friend of a friend, getting stopped at an airport for anything beyond undeclared fruits and vegetables, which has the penalty of "throw it away in this special bag."
PS: MRrainer: the US dollar has massively -appreciated- against the Euro and GBP (and most other European currencies, except not CHF) in the past couple years.