How do we create "curated collisions" in the hybrid workplace that helps us ensure that employees expand their colleague network and break silos?

I just came back to my desk from eating tacos with the CEO, our Western Sales Rep/Account Manager and the head of supply chain. I've been favouring WFH due to time constraints and gas prices, but I made it into the office today for free food.

A Google Form or something that can be filled in anonymously

A form that must be filled out weekly with the questions:

1) What did I learn this week

2) Who helped me the most this week

3) Something that could have gone better

4) Something that went very wll

or similar questions.

Regular meetings to not only disseminate company info, financial results, new hires, but also profile high-performers or particular departments in a rotating fashion

4-6 people are chosen from the company directory/org chart. They have to discuss online for 15-20 minutes in a remote meeting a topic that is broad enough for any department to be able to weigh in on. Company culture, charitable causes, etc.

Arrange something fun that can be done online (maybe a card game, movie watch party, trivia contest) for charity

Using gift certificates to Uber Eats or other services. I discussed the idea of an order synchronization app with friends as a business idea once.

Each department creates an elevator pitch for what they actually do. Each pitch goes head-to-head with another department and is judged by senior management or some 3rd party. Winning pitches go ahead to the next round/bracket.

No romance here, but create 1-to-1 meetings that only last 2-5 minutes and cycle through everyone in the company.

The other part of our taco lunch (mentioned in #1) was answering questions about our recent ISO 9000 certification. Answers were submitted by email, but there wasn't enough time (in my opinion) to get them done. If there's a topic that the whole company should have a better understanding of, and quiz questions can be created, a contest can be created. Most accurate answers (and whoever completes first in the event of a tie) wins a prize (prizes for 2nd, 3rd place, etc.) Take up the answers and have a (kind, sympathetic) laugh at any that were way off.