I have a similar problem but didn't want to start a new thread so I will post it here. Two days ago when I went to go start my car the lights flicked on when I put the key in the ignition, then I tried to turn it over and nothing, no cranking or anything, no dash lights or any lights to speak of in the car, power locks don't work or anything. So I thought maybe it had something to do with the battery, not being very electrically inclined, but then after waiting a few minutes and trying to turn it over, over and over again it starts and voila everything's fine. Then it worked for the next few times I started it up.
Today, comes the really odd part. My car unlocks with the key fob as I am leaving class, but then once I get in the car it fails to start, all the lights are nonfunctioning, etc again. I get out and look at the battery this time, notice a little corrosion but not much, not having anything on me to clean it off, I get back in and try to start it again and it works. Worked the rest of the day. SO, is this something wrong with a fuse, or some loose wiring? What's going on?