Lenses – Specialist

Macro / Micro – for close up photography
Fisheye / Extreme Wide – very wide lenses
Tilt Shift – To straighten converging verticals

Additional equipment for adapting lenses:
Extension tubes – for macro photography
Reversing Rings – Also for macro photography, allows you to put your lens on the camera back to front.
Teleconverter – to extend the focal length of the lens (usually 1.4x or 2x, occasionally built into the lens).