Not sure of anything that will hide them that you can put on beside paint. Many people paint right over them making them the same color as the house. It does hide them and unless you are by them you really can't see them. Hope that helps!!
Not knowing how you routed them and what the outside of your home is makes it difficult to come up with any ideas or suggestions for your particular case. Is the wiring on wood yes it could be painted or trim could be used to cover it. I have seen cases were with vinyl siding it was stuck under a panel I guess this could be done with aluminum siding too. I am not sure how I would try and hid wiring on brick or stone.
Most case the outside wiring on homes do not really seem to be noticed by most onlookers unless it is done sloppy. best way to make them unnoticed is run them neatly were they may be seen.