With a girlfriend studying psychology, it's unsurprising that I might find things like this out. In addition, being female, this particular lady can see right through me. I am totally transparent. Anyway, here are some things about the intrinsic bias my brain has. I think they may be a little more universal than just quirks of my personality. Perhaps they might be Western cultural traits. So, in my own words:

• I always think I'm wiser than I was
• I underestimate how much I eat and spend
• I underestimate my size/weight
• I overestimate my wealth
• I overestimate the amount of time I have free for things
• I underestimate the amount of time things take
• I overestimate the effort I've put into things
• I underestimate the effort things will require
• I overestimate my abilities
• I underestimate my failings
• I overestimate my achievements

I think all of this boils down to the fact that I'm a born optimist with an ego-centric view of the world. Maybe the problem in my case is that I reveal a lot of these things, perhaps other people are like this too, but by virtue of keeping quiet about it, don't get noticed.