Nxt is a blockchain platform developed by Jelurida, which is also developing the Ardor blockchain. Nxt's goal is to improve upon existing blockchain platforms with a modular toolset that enables users to create their own digital assets that can be listed on decentralized marketplaces. Nxt also features community driven voting mechanisms and has an architecture that separates the blockchain into parent and child blockchains.
The network is powered by the NXT token and has a Proof-of-Stake (PoS) consensus mechanism.

Stakenet is a blockchain with a unique Trustless Proof of Stake (TPoS) consensus mechanism that allows users to participate in the staking process without having to freeze their coins in the wallet. It's powered by the native coin XSN and is managed by its own masternodes. Stakenet (XSN) was created to build an ecosystem that allows easy and secure offline staking and cross chain communication. It has characteristics of Bitcoin, Dash and Peercoin, that were modified for their own purposes. XSN uses the Bitcoin Core, an improved Dash masternode architecture, and Peercoin's validation mechanism for creating new blocks.

Holo is a decentralized hosting provider that is built on top of Holochain. DApps can be set up and deployed with Holo hosting, as a decentralized alternative to Amazon Web Services, or other centralized hosting solutions.
Holochain is a protocol for creating decentralized Apps and is different from blockchain protocols in several ways. The main difference being that Holochain takes an agent-centric approach to their consensus mechanism, and has a different approach to validating value transfers.
The HOT token is used for paying for hosting services on Holo, and users can be paid for offering their computing resources.