Sometimes, rather than using a dedicated Virtual Table Top, it can be useful to use an online whiteboard - for example if you just need to make a collaborative map or you mainly use text in a shared space.

Jamboard Shared whiteboard with sticky notes, image import, laser pointer

Padlet Shared whiteboard with different template settings

Miro Shared whiteboard with different template settings

Google Slides To make collaborative shared maps, I also use Google Slides - just set a map template as slide background, and then everyone can add tokens / features etc as layers!