VNV Nation. Various albums but right now Of Faith, Power and Glory is playing. I don't think I've met a VNV album I haven't liked. Fabulous music for when you just need something playing in the background of what you're doing, or when you're just sitting on a ferry/driving/public transport and dream yourself away.
If you like ambient stuff like this is highly recommend
Atra Aeterna - Monolithium (Official Video):
http://youtu.be/k7G_YY62JZkThey do a lot of very spacey music all ambient stuff.
I listen to them a lot when I play Eve.
Boards of Canada is also another awesome "just drifting about" band. Dayavan Cowboy I think is the name of the Song I first heard by them, an excellent track.
Broke my heart when I found out they aren't actually Canadian