A remixed version of http://www.thingiverse.com/thing:742947
1) Slightly enlarged gap for head of hot-end - now fits snug
2) Different clamps:
a) Just for hot-end
b) Includes holder for 40mm fan
c) Includes holder for 40mm fan and 12mm Inductive sensor (new upload repositions the sensor a couple of mm)
3) Mount for fan to blow onto extruded plastic
4) Fan duct for fan (remixed from http://www.thingiverse.com/thing:582256)
May not look pretty, but doing the job nicely.
Uploaded a version with 19mm hole for 18mm sensors - although I cant test this version.