Not strictly caving, but if anyone is interested there is a live feed from the ongoing Bardabunga eruption here; http://www.livefromiceland.is/webcams/bardarbunga-2/.  The eruption is a classic Icelandic fissure eruption, and appears to to chucking out a lot of orange glowing stuff, so a god chance that there will be some new caves to explore once it all cools down in a few years or so.

Yes I have been following this. If this tube empties it could be 40 Kilometers long !
Now that would be a good lava tube .