On the "Most Active Users" page, each listing can show a featured website that the user has selected, driving traffic to the site of their choice. You can choose that website by clicking the "Edit Account Info" tab and filling the url in the "Favorite Website" section.
The system resets the count every day at midnight, Eastern Standard Time, and resets the weekly count every Monday. Thus, the count is not for the past 24 hours or past 7 days instead, it's based on fixed times and dates.
Userpoints are given once a piece of content (articles, websites and events) has been published by an editor. Thus, content that is submitted but rejected (or, just content that hasn't been approved yet) will not result in user points being given.
Click on the “My Network” tab in the member center. Look for the link that says “Invite New Experts into Network.” Use our invite feature and enter the email addresses of those you'd like to invite. For each person who signs up, you'll get 20 user points.
The user point system launched on June 28, 2009, and only actions that are performed after June 28th, 2009 can receive user points. Therefore, if you have an expert page or articles built before this time, there's no way to get fresh user points for these items.