as a potentially different use case, I use my tabs as a stack for reading things (where I push a link when I see it), and will then read through them all in a serial fashion, closing things I'm 'done' with. this generally leads to me having reference and 'to read' tabs open, in addition to things I like to have on hand (i.e. emails, workflowy, HN). this generally adds up to 15-20 tabs in my main window on average, going up to as much as 30-40.