BMI 127 depart LHR 13:30 arrive DUB 14:50 Fri Oct 13th.
That won't involve too much rushing at either end.
BMI 130 depart DUB 17:35 arrive LHR 18:55 Mon Oct 16th.
That'll allow reasonable amounts of time for getting confused at the Porterhouse at Monday lunchtime.
BMI 132 depart DUB 19:55 arrive LHR 21:15 Mon Oct 16th.
That'll allow a bit more, but I won't be home until nearly midnight.
Each of these itineraries are £63.55.
Travel to and from Heathrow will be about £15-£20, and travel from the airport via Dublin to the hotel and back will be some similar-sized handful of Euros. Neither are complicated enough to need planning in advance.
Convention membership €25, which is about £17.
Hotel, three nights at €99 is €297, which is about £200.
So that's just over 300 quid, plus whatever I eat and drink. And, as I discovered in 2004, Forbidden Planet is round the corner from the pub in Dublin.
It's all looking a bit believable. I might even throw in a few days with my brother in Kilkenny too.