Dublin

So some might call me crazy... And those that don't might be as loony as I am.
Tomorrow I fly to London via a stopover for ~7 hours in Dublin to have a beer at the Guinness factory and a haircut. (Plus the flight on the ArvoJet DUB to LCY will be cool).
Anything neato to do in Dublin that is off the beaten path but still near-ish to City Center?
Tomorrow I fly to London via a stopover for ~7 hours in Dublin to have a beer at the Guinness factory and a haircut. (Plus the flight on the ArvoJet DUB to LCY will be cool).
Anything neato to do in Dublin that is off the beaten path but still near-ish to City Center?