I believe that giving an Icon to someone who will honor it is a blessing to those whom you will give it to. They kind of icon you give would need to be appropriate to where they are in their life. I have given Icons to both Baptists, Methodists, and Lutherans that were of the major Feasts, the life of Christ, and of the Lord that were very welcomed and placed in or near their family "Prayer Center" thus creating a protestant icon corner without their being aware that that is what they have done. They have all spoken of the Icon "speaking to them" calling them to be "closer to the Lord". Isn't that a purpose of the Icon.
To our Catholic and Episcopalian friends, I have given preschism icons of Saints, the Most Holy Theotokos, as well as Festal Icons and have seen them mounted at their family Prayer altars/tables/corners. Likewise they speak of the impact the Icons presence in their home makes in their lives, often asking for suggestions on adding Icons to their homes.
So in conclusion, my experience has been very positive in prayerfully giving an icon to a friend or family member who is not Orthodox. The main gift I have received from doing so is having them more open to discuss Orthodoxy in a positive frame with the understanding that we are Christian not some kooky cult.