So their newest album is in my opinion their best so far, a very well developed sound which is a lot more chilled out than their earlier stuff, that said the production has really improved. Its not a new album, coming out in 2012 (yeah I've had it a while), but I still listen to one or two tunes of it daily.
First tune I'd recomend trying out is Kerosene, definately my favourite on the album
The second tune I'd recommend is mercenary, its just another one of their songs called sad eyes backwards and slowed down, but it packs a really trippy punch in comparison to their counterpart.
You can find more out about the Crystal Castles here and you'll be able to catch them at Glastonbury festival this year, hopefully they'll tour too.