Simon Harrer, Jochen Christ, and Martin Huber: remotemobprogramming.org
(see also pair)
External reference - Steve Tooke's report of the CucumberPro team's use of Remote Mobbing. Includes how they discovered the need and specific tactics they use to make it work for them.
As a comment on that post, Carlos Ble describes how they use a Wacom tablet to "remote" the use of a whiteboard, and their preferences for screen sharing apps.
Not specifically in the context of mobbing, but Nathan Arthur vouches for the https://www.owllabs.com/meeting-owl for multiperson meetings with remote participants.