Just schedule a regular meeting, and attend it - then advertise widely that you are available at that time and that anyone is welcome.
It's a great way to foster skip-level interactions, give help to someone who needs it, and just chat. It's really fun when a few people come in at once. Sometimes nobody shows up, and that's fine, too.
Give it a try!
Maker's schedule and all that. http://paulgraham.com/makersschedule.html
I personally do not have fun in these kinds of meetings. Even if they were held in person. My goal at the end of the day is to finish my work quickly and efficiently and try to get out a little early while meeting my obligations. Typically these chats eat up an hour or more and I end up working longer to make up for it.
They are extremely useful for helping newer engineers and answering questions but the "fun" chats tend to be just time consuming noise. It's entirely possible I have a different/maligned view of my relationship with my job but I just don't like giving any more than I have to for something that consumes 40-60 hours a week of my life.