Where can I view the user who has asked the most questions? Kind of like the leaderboard for most answers.
Top Askers on SE Data Explorer:
The top asker is Blankman who had 1371 at the last data dump (March 21, 2011)
I don't know about a leaderboard for most answers, but here is a query for that too — as we all know, Jon Skeet is the most prolific answerer by far.