Late last year, I purchased (via eBay) the UK versions of the first two Professor Layton titles.
Why, you ask? Honestly, I prefer the artwork used on the European versions of the games to the artwork used on the American/Japanese versions of the games.
Also, I prefer the clear plastic boxes used to house European DS games to the black boxes used elsewhere in the world.
Thankfully, I picked up both for about the same amount of money I would have spent on their American counterparts.
By the way, if you consider yourself a Layton fan, be sure to check out this awesome piece of fan art from Shitekudasai.
See also: 'Raise your hand if you own games you've yet to play' and 'To open or not to open, that is the question ...' and 'It's show-and-tell time!'