Great fun with broadband. Google Earth It's 11MB, but I think worth it. Ireland not covered very well yet, but it comes to life when zooming in on Mt. Vesuvios near Naples...............
I don't know about the NASA one but both google earth and the Mapflow maps used by myhome.ie allow you to zoom to a satellite image of some streets. With google maps the northside of dublin has much better image quality than the south side. I don't know how well other parts of the country are served by both maps.
Try http://maps.google.co.uk/ but detail for Ireland is not great.
You can zoom in and switch from map to a satellite view.
Probably the same level of detail as google earth, but nowhere near as good as the excellent interface of that amazing program!