I'm just gonna plug my submission real quick: check out Shomi. I just added the charting whatnot to it, which so far seems marginally useful but kinda cool. You can search for stuff like "recent comments by [username]", "top comments by [username]", "top submissions", etc. The UI is fairly OK; I'll make the search functionality more interesting after I get a couple hours' sleep.

Leave some suggestions and I'll see what I can tackle in a bit.