How many lines of code per day do you produce?
First, let me start by stating that there are many different metrics for determining the productivity of a programmer, and that lines of code ("LOC") plays only a small part. Other important parts include think, analysis, and debugging time.

If I understand the subject matter, have a good spec. to work from, and am loaded up with a good amount of coffee, I can produce approximately 1000 lines of debugged C code per day.

Scripting languages are usually much easier... I once wrote and debugged a little over 7K lines of object-oriented PHP in 48 hours straight.

LOC is useless when it comes to working on something that isn't directly related to LOC such as parsers built via parser generators or applications that use a lot of copy-and-paste programming.

How well do you comment your code?
I always comment my code. If I'm working with a team on a long term project, I'll usually comment every 20 lines. However, if I'm working on a short term project, I will usually comment generally every 5 lines and extensively on all business-critical sections of code.

Are you an egomaniacal son of a...?
I don't think so. A great deal of programmers are, and I've paid my dues, but I've found that it doesn't really get you anywhere.