[ivvve]

IWGB and UVW (International Workers of Great Britain and United Voices of the World) are examples in the UK. IWGB in particular has done great work representing some of the most precarious workers in the gig economy, a risk that bigger unions cannot or will not take. Partly this is due to the UK unions playing it safe with direct action such as strikes, since labour laws in the UK were made rather stringent since Thatcher and the NUM had it out in the 80s.

This is a great article about them. Maybe paywalled, sorry!

https://www.ft.com/content/576c68ea-3784-11ea-a6d3-9a26f8c3c...

If you Google "IWGB deliveroo" or "UVW St. Marys" you will find interesting case studies where each have represented delivery riders and nurses and won concessions where a bigger union wouldn't have bothered cos of the risk involved. Echoing the comment a few levels up, this can definitely be seen as a "disruption" of what a union is or is expected to do.