True office productivity: Emacs remote collaboration (CRDT).
To create documents, presentations, spreadsheets and the like, nothing beats Emacs with two or more users collaborating simultaneous in the same buffer.
Qianton Hong has made Emacs collaboration very straightforward, with CRDT.el. In addition, his documentation is very clear, meaning that it is really easy to get this to work.
In a nutshell, in Emacs you use crdt to indicate which buffer or buffers you wish to share. You can include a password if needed. Assuming you correctly set up the intermediate host, all your co-workers need is this URL and presto! you can start collaborating on whatever is in the shared buffer.
Qianton gave an introduction (youtube) on CRDTat the NYC Emacs meeting on 3 November 2020. It was put to use by the Emacs Research Group, talking about their online collaboration a year later, at the Emacs 2021 conference.
At the NYC Emacs meeting, Qianton said a future version could even make collaboration possible without the need for a central server. Making it fully distributed would probablye mean another 1000 lines of code. "It is doable on the current infrastructure", he said