M2HTML: Documentation System for Matlab in HTML [Link]
M2HTML is a powerful tool to automatically generate HTML documentation of your Matlab M-files. Its aim is to be a successor of the Perl script MAT2HTML from J.C. Kantor, including new features.
This toolbox includes the Template toolbox, thus allowing for a full customization of the output layout. It also uses the syntax highlighting engine from Highlight.m.
Doxyen filters for Matlab scripts [Link]
Ben Heasly has written a filter for doxygen that converts MatLab scripts (including the new object oriented features) into something doxygen can understand. An alternative filter is provided by Ian Martins. There is also one by Fabrice which can be found on Matlab Central.