The Internet site http://www.wien.info/article.asp?IDArticle=10069 offers information on hotel booking, sightseeing and other useful information for visitors. Some hotels offered discounted rates for UN visitors. Please, ask when making your booking.

Those who want to stay really close to the venue may want to try these hotels:

Starting from 52 euros:
http://www.sportcenter-donaucity.at/
(Guest house. The website is only in German but you can send them an email or call)
E-mail: zimmer@sportcenter-donaucity.at   
Tel.: +43 1 269 96 30    

Starting from 85 euros:
http://www.residenzdonaucity.at/index.htm

Starting from 108 euros:
http://www.viennauno.parkinn.at/

Starting from 136 euros:
http://www.nh-hotels.com/nh/en/hotels/austria/vienna/nh-danube-city.html