Rather than visit every SOFU, SE, and meta site every day to see if anyone has answered/replied/voted on my posts, I would like to have one page that consolidates all of these notifications.
This has been asked a few times. Here is something that might be what you're looking for:
Disclaimer: I wrote it.
In addition to the topbar (which replaced the supercollider), you can see all your responses (not reputation changes) from your network profile under the inbox tab. You can get to your network profile from the accounts section of any per-site profile page.