This is a good service if you would like to send a direct download link to a file you keep in Google Drive
Hosting a dedicated game server? Hosting a web server? Want to open up Microsoft's Remote Desktop protocol on your computer to the internet so you can connect remotely? FreeDNS (afraid.org) can help here. Create customized addresses that redirect to either IP addresses or other web URLs. This is the service I use to have http://asm-wiki.us.to redirect to this Google Sites page.
Downloads a high-quality mp3 file from a YouTube video. This is useful if you want to get a mp3 file for a song that's not on Spotify, to add yourself.
Use the iTunes album art downloader Ben Dodson created if you need to, say, manually add album art to a MP3 you downloaded off YouTube.
My go-to movie torrent site. Old but gold. Quality is not the absolute best, and they still use the x264 encoder as opposed to the superior x265, but they have pretty much everything. Popular enough to have lots of seeders and almost every movie you can imagine.
For downloading eBooks. Very useful for college students, for reasons I'm sure you can imagine.