Scotch Broom
Cytisus scoparius
Basketry
Scotch broom works wonderfully for making coiled baskets in a manner similar to pine need baskets.
Peter Bauer of Rewild Portland makes baskets out of invasive plants including scotch broom. See some of his baskets on his personal site along with workshops hosted by Rewild Portland.
Juliana of Plants are Teachers has run a workshop making coiled baskets out of scotch broom stiched with himalayan blackberry fibres.
Fibre
Sharon Kallis has processed scotch broom for spinable fibres. She details the process in this video.
Carving
Francois Lavigne carves cutlery and buttons out of scotch broom working. His work is for sale at McMillan Arts Centre or watch a video of the process.