Every year I say to DH "we must get some of those lovely icicle lights on the front of the house". But every year I'm defeated by the whole issue of how to power the damned things.
We live in a bungalow, none of the windows can be left open for a cable (any anyway, surely it would be draping unattractively across a room, even if we did do this). We have an outdoor socket, but it's miles away in the back garden, and all of the lights I've seen say that the transformer needs to be plugged in indoors anyway. No porch, garage, shed or similar.
Do you have holes drilled though your roofs, or something?