The Mahones are great too. Irish punk similar to the Pogues.
There are some really good Newfoundland bands who play lots of Irish folk, but without the angst of punk:
Great Big Sea
Spirit of the West
Irish Descendents
Also, if you like both Flogging Molly and Dropkick, you should check out the Mighty Mighty Bosstones. They're not as celtic influenced (although you can hear it sometimes in their stuff), but they're from the same label as the other two bands. They have a very Boston-Irish punk sound, with ska elements. See if you can find the song Riot on Broadstreet.