London and Dublin aren't cheap either! Dublin used to be, but ever since the Euro things have changed dramatically. I first spent time in Dublin in 1980 and didn't go back until 2001; what a difference! In 1980 Dublin was a mess...trash all over the streets, the Liffey was an open sewer, and people smoked everywhere, including movie theaters and the no-smoking cars in trains. I watched Raiders of the Lost Ark in Dublin in 1980, through a thick haze of smoke in the cinema. Dublin was cleaner though still noisy and chaotic in 2001, and the city centre was markedly upscale compared with how it was in 1980. I'm sure it has changed even more since I was last there. But a few tips for Dublin:
1. Temple Bar, which used to be the last neighborhood you'd ever want to visit in Dublin, is now definitely worth a ramble. Lots of cool shops, pubs, galleries, and restaurants.
2. The reliably best traditional Irish music sessions in town happen at The Cobblestone (in Smithfield) and Hughes' Pub (19 Chancery Street). Smithfield can be a bit dangerous late at night, but "late" in Dublin is 2am onward. Those two pubs usually have music every night, and they're sessions (informal jams) with some of the country's best traditional musicians...it's a much better experience than a concert, and there's no cover charge.
3. Statues: Free entertainment...be sure to check out the statue of Molly Malone selling cockles from a wheelbarrow, affectionately known in town as "The Tart with the Cart," as well as the Anna Livia statue and fountain (which used to be right in the middle of O'Connell Street but was taken down a few years ago; I believe it's been relocated since then), known locally as "The Floozie in the Jacuzzi."