services to replace: any file hosting
File sharing using WebRTC, ideally for IM which not supported DCC.
Cjdns is a networking protocol and reference implementation, founded on the ideology that networks should be easy to set up, protocols should scale up smoothly, and security should be ubiquitous. .
services to replace: Dropbox
Google Drive
MEGA
Microsoft OneDrive
Box
MediaFire
Yandex.Disk and more
protocols to replace: https://alternativeto.net/software/ftp
protocol to replace: HTTP
this compilated kademilia + bittorrent + git + CDN
a lot of time will pass before he accepts, however, he would solve the problem of the almost all services
centralised services to replace: YouTube
Vimeo
Dailymotion
Metacafe
LiveLeak
Also worth mentioning: PeerTube
Protocols replace: https://alternativeto.net/software/email
email is great protocol which is de facto standard hovewer does exists experiments with p2p version.
Also worth mentioning Jami
Ricochet
Bit Chat
Cryptocat
RetroShare
P2P communications have a cons that isn't federated so not recommended every day. one exception is here https://alternativeto.net/software/riot-im/ but isn't P2P.
centralised services to replace: Google Search
DuckDuckGo
Qwant
Microsoft Bing
Yandex.Search
Gigablast
Yahoo! Search ....
Problem is with non-free database. Sure, does exists project like Searx which is metasearch in some engines hovewer it's just prosthesis.
centralised services to replace: Facebook
Twitter
Google Plus
VK
Gab
Tumblr ...
mastodon worked similar to XMPP, is decentralized, fully interoperable, federated using ActivityPub
Know any P2P VPNs?
Tor ?
I2P