There's also a collection of objects for performing fuzzy logic operations. The Lobjects are included in the Max third party objects distribution, but you can also download the latest set on the Peter's Lobjects page. At last count, Peter Swinnen had 28 objects listed on his site . Must-haves include udraw, a replacement for the Max LCD object, and phonedecoder, which can listen to your Mac sound input and decode touch tone signals. MMyneta has a package of objects for list manipulation and performing mathematical operations on lists.
Source code is available.
There's also a really nice 3DMF viewer where you can reorient the display of a 3D image under Max control. There are also links to other max sites of interest. Timothy Place has a collection of interesting Max and MSP patches and externals on his software page including granular and vocoding applications. Monolake provides its MIDI step sequencer and a couple of MSP goodies on its download page . You can also get some of the special Max and MSP objects jhno has created for these applications.