Just discovered this!

[Michael]

...

[Michael]

Rik,

Better use ALT button for this;
If you make a habbit of this,you'll find that if you use the shapebuilder tool will also draw straight lines(alt not ctrl)
If you use the ctrl+alt,it draws straight lines at your angle constraints
and if using ctrl+alt+shift it is an eraser with straight lines in angles
This also applies for the eraser tool

Hans

but there's a snag with that one which IMHO is a bug: when using a brush as a line, the ALT trick doesn't work anymore. bummer.