Ár nDraíocht Féin: A Druid Fellowship, a group focusing on recreating (in a modern context) many various religions of ancient Indo-European peoples. Though it's the largest Druid group in America, until recently (luckily a Protogrove just started in my area!) I haven't been able to attend any rituals with other members.
Luckily for all members outside of driving distance of a Grove, the idea of 'web rituals' was recently talked about on the lists. Nicholas Egelhoff, a member of the Norse kin (a group within ADF devoted to the Norse pantheon) set up the first 'Druid Moon Ritual' on Google Hangout. Called the 'Druid Moon Ritual' because of its location on the 6th day of the new moon, about eight people were on video (from different locations!) performing the ritual for a larger group of ADF members. You can watch the video of the ritual here on youtube. There were a few technical issues at first (which is why I linked it some 30 minutes in), but overall I felt it was a wonderful success! The use of more tech-heavy imagery, as well as the invocation of pioneering technology Ancestors, was an amazing touch that really made the ritual work.
Before trying it out, I wasn't sure how to feel about virtual ritual. On the one hand, coming from a Christian background, I'm used to the notion of believers from around the world being able to 'link together', as it were. On the other hand, it's a concept I've tried to minimize in my own practice - believing as I do that contact with land spirits is best done on the land, talking to ancestors is best received near their graves, etc; my spirituality is generally more about direct contact than linking energy over great distances. And yet, once the ritual begun, I largely forgot my misgivings. The energy did flow. Though the Kindreds were being invited and sacrificed to many miles from me, I still felt Their presence.
The leaders of the Druid Moon Ritual are hoping to have one each month on the 6th day of the new moon. If you're interested in watching or participating, you can check out ADF's Google+ page, where I believe more announcements will be made as the time for the next ritual draws nearer. Personally, I'd like to see as many people as possible - it's a wonderful experience, and I think largely due to its nature, would only become more powerful as more people join in.