I like tasteful ones - there is one house near us here that have a big tree in their front garden and they have just put hundreds of white lights on it. It looks lovely.
We have a tasteful white star in the window of the front door.
I did buy some outdoor lights but DH was worried about the security aspect of being away for Xmas and them not being on so we haven't bothered.
My Dad has bought a few more things to put up in the windows - my sis asked him was he entering a competition! He does it for the grandchildren which I think is lovely.