Energy drink
Sometimes when I need to power through some editing job I'm not too exited about, I just slam an energy drink. Then just start editing, and you'll have too much surplus energy to stop.
It's all about getting into the Zone. I usually start by trying to psych myself up via thinking about how cool I can make some part, or how people will react to this or that, then once I have something I really want to see done, it's no problem. Sometimes I listen to energetic music such as the crystal method to get the movie flowing in my head.
Hope that helps, I had to edit a 22 minute episode 5 days a week one year, and believe me, I've been there, staring at the premiere icon buy somehow unable to bother pushing it.