When looking at a users profile page or while looking at any other link to a community/account, it would be great to have an icon next to the community/account link or some color coding to let me know roughly how long it's been since someone last posted.
Or just retire communities/accounts that haven't been logged into or nothing posted for a certain amount of time.
I'm tired of coming across what look like cool communities/accounts just to see no one has posted for four years. Something to expire them or warn me they are abandoned to save me the time of going and looking at them would be great.