YSL Touche Eclat
Technically it's a highlighter and not actually a concealer, but in reality concealing is what it does best. If you've got dark circles under your eyes, blemishes or just need a bit of help to quickly brighten up a tired face, this stuff is great. Be careful though- apply too much around the eyes and you'll end up with Reverse Panda Effect - see Caprice for more details.
Available from Department stores, about €28 (or get your boyfriend to get it for you in the duty free - score!)