We live surrounded by electronic devices of increasing complexity, usually having short lifetime and high environmental impact. How can we, from fablabs, contribute to reduce this waste of resources? What role should we play in such a “resource-consuming” environment? We describe how within a collaborative environment and with few technological resources, many electronic devices (or furniture, or clothing, or vehicles) can be repaired, improved, and reused. We describe what we consider good uses of material resources inside a fablab, from design to manufacturing, including sources of waste materials. We also describe briefly some repairs and maintenance we must carry out on our machines, common to many fablabs. The knowledge to repair an electronic device is valuable since it allows studying real problems analyzing their causes (technical) and consequences (environmental and economic). We give several examples of educational uses of appliance repair: from workshops for curious people, within global networks such as Repair Cafe, to official subjects for engineering students, within official degrees at University of Extremadura. Finally we describe how a regional company, La Hormiga Verde, in Spain, has based its business model on a collection network of electrical materials. They are repaired and sold; or destroyed, separated and selled globally by weight, by personnel at risk of social exclusion. Fablabs can collaborate with this type of company since we can help to further value the materials they generate through the process of design and manufacturing.