How do you deal with plot holes?

Plot holes are probably every writer's/creator's nightmare and I don't think they can really be avoided. How do you deal with them?

I don't think I really figured out how to handle plot holes (but, granted, I'm not writing a book atm nor am I working on any real story myself) - I usually figure things at the very last second (while I'm gming for example).

Since so much of my story is planned in advance, I usually iron out plotholes before I get to them ^^;;;

Luckily with writing, it's easier to fix it before you get there, or go back in editing and make everything more consistent (for smaller inconsistencies x_x)