Is It Down Right Now? - Network & Admin
HakuNeko - HakuNeko is an all-in-one cross-platform utility that supports you to download manga and anime with various website support.
UPDOWNtoday - UPDOWNTODAY allows you to check whether the website is down or not.
Hitomi Downloader - Desktop application to download images/videos/music/text from Hitomi.la and other sites, and more.
Site Down - Site down outage and downtime reports from SiteDown.co
HDoujin Downloader - A powerful doujin/manga downloader that supports hundreds of different websites.