Note: With anything but the bigger hotel chains (eg Jurys/Comfort Inn), or places with a single, standard rate across the board (eg Bewleys), it's often worthwhile asking if "that's really your best rate", when booking - it doesn't cost much to try it, and many places will give a discount to anyone cheeky enough to ask
The cheapest hotel within walking distance of the conference is probably \[http://www.bewleyshotels.com/ballsbridge_hotel_dublin.asp Bewleys Hotel Ballsbridge\], at 99EUR per room, per night. \[http://www. schoolhousehotel.com/ The Schoolhouse Hotel\] is somewhat more expensive, but has a very nice restaurant & pub attached. Wiki Markup
Slightly further away, still on the hotels, the \[http://www.comfortinnhoteldublin.com/ Comfort Inn\] on Parnell Sq is about a 40 minute walk, or ten minute bus journey from the conference hotel (46A bus route goes along Parnell Sq/O'Connell St, and stops directly outside the conference hotel). Wiki Markup
For cheaper, non-hotel options, there are quite a few good B&Bs in the immediate area - the \[http://www.ireland-bnb.com/search.html?county=Dublin&town=Ballsbridge Bed & Breakfast Network\] has listings of some of them. Wiki Markup
\[http://www.softguides.com/dublin/accommodation/Pembroke_Hall_Guesthouse_Dublin.html Pembroke Hall Guesthouse\] is pretty close by, and comes in at 68 Euro per night. Wiki Markup
Cheaper can be gotten of course, but mainly in the City Centre, which is about a 20 minute walk away. One of the closest real budget hostels is \[http://www.avalon-house.ie/ Avalon House\], and it's about a 15/20 minute walk away. Wiki Markup
If you're searching online, try to keep to the "Dublin 2" and "Dublin 4" postcodes, and you can't be too far away. Some of Dublin 6 is very close by too. Temple Bar is a serious party-zone, so be careful - don't stay there if you're not into being out all night! Gardiner St and Talbot St have some very cheap hostel accommodation too - but you do get what you pay for, and they're not the best part of Dublin, to put it mildly.
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