Flogging molly - requiem for a dying song
Flogging molly - drunken lullabies
The Real McKenzies - Pour Decisions

those 3 are great... especially the last 2
My Guitars:
Gibson Les Paul Studio
Epiphone AJ
Ibanez Strat Copy

Orange Tiny Terror Head
Old beaten up Peavey cab
Marshall MG30DFX
anything by Primordial....although I do not believe they are particularly celtic sounding, they are Irish and kick a lot of ass.
Nerve threads decoding the stream of the reality-inverting revolution
The patterned untruth of non-dream:
The closed-eye
visual delusion.