Bandcamp Shuffle is a Firefox add-on that will shuffle collections on Bandcamp pages.
You can download the add-on for Firefox here.
Once the add-on is enabled you should see a button in your Firefox address bar when viewing a bandcamp.com page. If the page contains a collection of albums it will shuffle the visible albums (this is only temporary - refreshing the page will reset it to the original order).
In the add-on Preferences you can also enable a mode to first show all albums in the collection before shuffling. This is a more useful approach, but it's turned off by default as it relies on a private Bandcamp API and may be unreliable.
Feel free to create an issue if you find any issues or would like to contribute to the project.
Distributed under the MIT License. See LICENSE for more information.