I find this question a little more pertinent now, given Stack Overflow Careers and Joel's assertion that reputation is a good indicator of programming ability.
The majority of my reputation comes from either insanely easy questions or meta-ish questions. Sure we have the meta thing policed, but what bugs me is the huge difference in "plus rep" you can receive for providing pretty simple responses in popular technologies (such as C#) against excellent answers in more niche ones. I've seen awesome posts in niche techs that have like + 30 tops, whereas there are others that are kind of "meh" in a popular technology with +100 or more.
Is there anyway we could adjust the voting system to address this? Bounties help a little, but I was thinking more along the lines of being able to +x an answer or even gift reputation to others for specific answers that really helped.
I appreciate that answering the question in the title is the obvious thing to do but I'm much more interested in discussing systems to address this issue that don't also open up other cans of worms.
For example, if we had a feature where I was allowed to give an extra 100 reputation to an answer per day because I have greater than X reputation where would such a feature fall down?
Or are we agreed on the premise that such a system is impossible, and the current one is the one that "sucks least"?