I'm starting this discussion because I was in danger of hijacking the Icelandic volcano thread. I started using the Mila Icelandic webcams to watch the eruption at Holoraun (the Bardabunga webcams), but lately I've seen the aurora borealis quite a few times on the other webcams, particularly the Thingvellir webcam www.livefromiceland.is/webcams/thingvellir/, although the lights can be seen sometimes on the Hekla and Jokulsarlon ones.
Another OP posted a link to the Hotel Ranga aurora cam, which is here: www.hotelranga.is/northern-lights/northern-light-webcam/
I am posting a couple of pics below for comparison to get you started. The first is a lovely aurora shot at Thingvellir from September, then a more blurry one from last night and a normal dark evening shot.
If you can find any other lovely aurora cams please post links (and pics) below. Happy hunting!