It has actually been noticeably quieter here today, and apparently the are around where I used to live (Richmond/Twickenham/Esher) has been beautifully peaceful, all due to the suspension of flights from Heathrow. On the downside, supermarkets are starting to run out of more 'exotic' fruit and veg because there is obviously no air freight into the country. I had heard reports that some ash was coming to ground in the far north of Scotland, but as I understand it, there wont be any chunks of rock or even visible matter falling from the skies any time soon...
It's the same here, only with flights to and from Copenhagen.
I live in one of the suburbs surrounding CPH, and we usually get a lot of planes coming in, heading for Kastrup (Cph. airport), and it's very quiet and peaceful here now.
I've got to admit that I enjoy it, because sometimes those planes come in so low that it almost sounds like they're going to land in front of the apartment buildings on the lawn out here, so the peace is very welcome here; I'd just wish that people weren't stuck in all sorts of places all over the world, it must be incredibly annoying not to be able to get back home.
I've got a friend who lives right next to the airport in Kastrup, and she has told me that the quiet's almost eerie, it certainly doesn't feel normal to her and her husband.
Another friend is stuck in Greece, and now her husband - who's home alone here in Denmark - gets to feel what it's like being a full-time mom for two small kids....now if
that ain't poetic justice, somehow!

Ah well, they'll sort it out eventually, they've got family who can help just in case dad's stuck with a problem with the kids.
But still...
The hotels are full with travellers who can't get home these days, and the hotel owners certainly earn a good deal of money on that, and people find other ways of getting home somehow - by train, bus, car, whatever, and the rail companies and bus companies is suddenly very busy, so eventually people will get home one way or the other.
But it is a nuisance, and now the vocano's eruption has increased in strength, so all flights are cancelled at least until 2 o'clock sunday afternoon, danish time, according to Naviair.
EDIT sunday morning:
All flights are cancelled here until 2 o'clock tonight.