Norwegian (DY) are pretty good, too (and they have assigned seating, and you can snag the exit row for no extra charge if you check-in early enough!).
AFAIK, they are the only airline with a 2-bag (2x20kg) allowance within Europe. You pay a reasonable admin fee (50 kroner?) for each bag you check, but this can save you loads of money over other LCCs and even FSCs if you're carrying a lot with you.