According to the developer's [website][1]:

"MIDKontrol is a powerful program which lets you control MIDI gears by
sending preset or programmable continuous controllers (cut off, reso,
attack, decay, release, reverb...) or note on controllers. The random
capabilities let you search for new sounds or effects with a
mouseclick! MIDKontrol can also be used as a powerful MIDI filter.
Toggle from 4 different color backgrounds !

Requirements
Any 68000 or Power PC macintosh running from System 7 to 8.5 (Must be
OK under Mac OS 9).
A MIDI interface hooked on the modem port.
A MIDI gear compatible with continuous MIDI controllers messages.

Technical tips
MIDKontrol works with its own MIDI drivers, so you don't need OMS nor
Apple MIDI manager. Nonetheless MIDKontrol is compatible with this
previous drivers.
MIDKontrol is compatible with almost all MIDI gears of the market
(including standards like XG,GS,TG,General Midi).
For the rest, the online help is enough!

..

MIDSensor is a basic but powerful program which lets you control MIDI
gears with mouse or joystick moves in 2 Dimensions. Select 1 or 2
preset or programmable continuous controller and start waving upon the
window ! Simple but lethal ![Wink][2]

I use it in conjonction with a Yamaha RM1x sequencer/expander to
modulate sounds in real-time. Should work well with Roland MC303-505
and all MIDI gears that deals with Continuous Controllers (at least
Pan and Volume).
Obviously, all the MIDI events are recordable.

Requirements
Any 68000 or Power PC macintosh running from System 7 to 8.5 (Must be
OK under Mac OS 9).
A MIDI interface hooked on the modem port.
A MIDI gear compatible with continuous MIDI controllers messages.

Technical tips
MIDSensor works with its own MIDI drivers, so you don't need OMS nor
Apple MIDI manager. Nonetheless MIDSensor is compatible with this
previous drivers.
MIDSensor is compatible with almost all MIDI gears of the market
(including standards like XG,GS,TG,General Midi).
For the rest, the online help is enough!"

Archive includes 68K and PPC versions, as well as BW versions for
compact Macs/OS6.

Compatibility
Architecture: 68k PPC

  [1]: http://moukraine.free.fr/html/indexf.html
  [2]: http://macintoshgarden.org/sites/all/modules/smileys/packs/Roving/wink.png (Wink)