If you want to piss off an electrical engineer, tell them that future electronics might be built using a room-temperature metallic glue instead of conventional soldering techniques. Despite the tedium, burns, bad joins, and dangerous lead fumes, soldering is a prized and hard-fought skill. It's also unavoidable: a technique central to absolutely everything to do with building and repairing electronics at all levels.
Materials scientists at Northeastern University in Boston are daring to suggest, however, that its days may be numbered. This is thanks to a recent creation dubbed MesoGlue: a "revolutionary joining solution that lets you attach items together with a metal bond, at room temperature." Soldering without the heat, in other words. The new material is described in this month's Advanced Materials and Processes.
The origins of soldering are usually put at around 5,000 BC. Metalworking had already been around then for 7,000 years or so, but the idea of using molten metal to join stuff together came later with the discovery of naturally occurring alloys featuring lower melting points. Earlier solders were made of gold and tin, with the tin-lead combination employed in contemporary electronics appearing some time during the Roman empire. In other words, soldering is old as hell.