LM Vienna
I agree with all the other replies about the LM (I've stayed there 3-4 times). Fantastic hotel, super modern, great service. I'm an SPG Gold and had a complementary fridge with beer, water, and juice refilled everyday.
The location is great too - ~ 1 block from the Opera and the Kartnerstrasse (the main pedestrian street).
I am trying to recall, but I am almost positive that the internet (wired) is free too - so hard to find in Europe.