THIS IS FOR CHROME.
If requested I will create a Firefox version.
Check hnuser-screenshot.png to see how it works.
How to Use?
-Download the Folder
-Extract it somewhere.
-Open chrome and type: chrome://extensions
-Select the folder you extracted.
-Select LOAD UNPACKED and it will run on news.ycombinator.com when you hover on a user after 0.5 second.
How to change the delay?
-Change the value near the bottom of content.js: "}, 500);" to whatever value you desire.
-Do not change it to 0 so it won't request immediately when you hover.