What are some good techniques to get you motivated to finish something you have lost interest in?

I agree with zuriki. However, there are some issues with the phrasing of the question: if you've lost interest in it, why do you want to have motivation to do it? If you want to be motivated to do something, that usually means you are interested in it (and I'm sure that's what you mean).

If you feel blocked from being able to act on a goal, I believe it's important to post it up on the wall somewhere in your house, and then leave it. I actually wrote a hub about my strategies for this here: vdelarosa.hubpages.com/hub/How-to-Get-Motiv.

Take a break. Getting your mind out of the project for a period (short) is a sure way of rekindling the passion that got you started in the first place.

Say to yourself 100th times that you love doing the chore and visualize yourself doing it.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.