There's Burner (https://burnerapp.com) and I'm sure there are at least a handful others around. - Source: Hacker News / 10 months ago

There are companies that will let you have a virtual mobile number. 160.com.au is one such provider. There are also "burner" apps that will allocate you a mobile number and send the sms through their app. burnerapp.com is an example. I believe both of these providers can be trusted. Source: over 1 year ago

Tools like Gather Town to encourage more ad hoc group interaction. One team I led used this tool daily for nearly a year, and the frequency and quality of our interactions were on par with an in-person office. - Source: dev.to / 10 months ago

Well, after some more googling I found a good candidate: gather.town if anyone is interested. Source: about 1 year ago

Our Guides will host live sessions throughout the April 28-30th weekend in our custom http://gather.town space to spark connections and learning among global participants. You'll form diverse teams, uncover shared goals, and explore a wide range of issues through the lens of Complexity! Source: about 1 year ago

I'm really digging gather.town for this. Our team has it set up & the ad-hoc "meetings" have gone up tremendously. You can choose to engage or not but it seems to be way more informal than slack for a quick sync, which is a gigantic strength imo. Source: over 1 year ago

As mentioned above by @yowzas648 you should check out https://gather.town We started using it this week with my team and it is game changing, it does exactly what you just described. Source: over 1 year ago