The eigenmode of surface plasmon are obtained for different geometries. The results are valid for voids and for particles and give the eigensurface mode of spheroids, paraboloids, cones, and multi-edges. Limiting cases, obtained by asymptotic development, or particular cases useful in some physical situations are studied in more detail: spheroïdal or paraboloidal needles or craks, spheroidal or paraboloidal disks, whisker diode geometry, and blades perpendicular to a plane.