The 3D Viewer plugin can display 3D stacks via volume rendering, isosurfaces or as orthoslices.
The TrakEM2 plugin can be used to annotate images non-destructively.
The TrakEM2 plugin offers a range of manual and semi-automatic segmentation tools.
The SIOX plugin provides semi-automatic segmentation of color images via Simple Interactive Object Extraction.
The SPIM Registration plugin provides fast, reliable and high-precision registration and fusion of Selective Plane Illumination Microscopy data as well as other 3d multi-angle image acquisitions.