If it's more than a month or two I politely enquire whether or not said person has read/watched the item in question. If they haven't my enquiring should bring their duty as the person borrowing something to their attention which hopefully speeds up the process. If they have, I'll pick the item up the next time I see them. I used to be a lot more protective of my stuff, never allowing anyone to borrow anything. I don't know what changed, but right now it really doesn't bother me all that much if a friend is somewhat leisurely with whatever they've borrowed.