[Bam] from the LulzBot forums has successfully printed metal using his 3D printer and a Budaschnozzle ... Be warned though, the solder will corrode brass and aluminum, and [Bam] notes that ...

Face it, we’ve all at some time or other looked at our hot glue guns, and thought “I wonder if I could use that for 3D printing ... he help of a piece of brass tube.