There is a shopping centre called "St. Stephen's Green" just off of Grafton St (city centre) Ask anyone and they will know where it is! There is a shop in there called Cogs - The Brain Shop, that has some puzzling stuff - for store directions see here: http://www.stephensgreen.com/storeinfo. ... Brain+Shop
Also in the same shopping centre there is an art and hobby store that has a very limited selection of brainteasers - http://www.stephensgreen.com/storeinfo. ... Hobby+Shop
- but I doubt if you would find anything unusual here but it's always worth a check!
Enjoy your trip, I hope the weather keeps up for you as it has been very nice here for the last week - there is a nice park right beside the shopping centre where you can relax if it does!
ps if anyone else knows of other shops I'd love to hear about them too as the ones I've mentioned are the only ones I know!