Why are there a bunch of users with a 100ish reputation that have no answers and one or two questions that don't have enough up votes on them to equal their reputation?
Just click on the profile of someone with 100ish rep. I haven't found one yet that had enough votes to match the reputation.
You get 100 points for linking your programmers profile with any other stack exchange profile. This makes your points 101 even before you answer any questions.
You get 100 reputation bonus when you link your account to another one in the Stack Exchange network with more than 200 points.
By getting 200 points on site A (Stack Overflow) you've demonstrated that you know how to use the system. Giving you a 100 point bonus on site B (this one) is a way of helping you over that initial hump so you can do the basic things like vote up and comment. Voting down needs a reputation of 125 so you have to participate in this site to be able to do that.
