Hi, FLo!
Please describe in detail how the tool should work. And the practical application of a tool? Maybe something will prompt.

One way would , i can select two path's (with the direct selection tool) of two different objects and push the Play button of scriptographer and than the second object (whole Object) rotate to the point when both selected path's are parallel.

An other way would be a new type of smart guides. The new smart guides appears everytime i rotate an object an it is parallel to an other. But i think this version is much more difficult than the first one.

I hope someone know a solution.
Thanks

Select two objects. Click botton "Start". If the "parallelism" of objects is "false", one of 2 objects starts rotating. The rotation stops when the "parallelism" is "true".
The problem is this? Ok. ie essential function of the definition of "parallelism" of the two objects..cool