Since the weather turned too cold to do much outside, my husband and I have started watching the Lord of the Rings trilogy - they are so well done, we never get tired of watching them no matter how many times. 
There were quite a few parallels between LOTR and Harry Potter.  This post is kind of in-line with "Insert's" earlier one (haha - it always cracks me up to call you that, we need to find a better way to refer to you in blogs).  The dead bodies in the water that grabbed Frodo when he fell into the water was like the part where Dumbledore and Harry go to the cave to get the fake locket.
A lot of sites have mentioned that Dobby is similar to Gollum, but I disagree. Dobby believes in the virtues of individuality,  freedom, and personal choice.  Unlike Kreacher and other elves, he has no internal conflict between his duty to his "masters" (the Malfoys) and his own self-dignity and sense of right and wrong.  Though he seems conflicted when he is magically bound to them, once he is freed, he feels no loyalty to them, unlike Winky and Kreacher.  Also, Dobby adores Harry from the beginning, and never feels betrayed by him.
Gollum's internal conflict is between his desire for the ring and desire for happiness and freedom from the ring, and is so strong that it dominates his every thought and action. He is not beyond redemption, though, and becomes loyal to Frodo when Frodo shows him kindness.  Later, when he feels that Frodo has betrayed him, he succumbs again to the power of the ring.