In public browsing (in Firefox) I'm unique. In private browsing I'm 1 in ~17000.
Interestingly, removing some of the non-standard fonts I have installed made me unique, even in private mode. This surprises me, because I have some pretty unusual fonts installed.
edit: And actually, now that I test again, it does find one other match even in non-private mode. I guess that it's counting each me as a new person each time I do it, even though I'm connecting from the same IP with the same exact browser configuration.
Not surprising given that fonts tend to come in groups---did you remove all your nonstandard fonts? If five people out of a million install the same unusual font pack, and one removes all but one font from the pack, that one will be a unique even though the configuration is "more like" a common one.
Interestingly, removing some of the non-standard fonts I have installed made me unique, even in private mode. This surprises me, because I have some pretty unusual fonts installed.
edit: And actually, now that I test again, it does find one other match even in non-private mode. I guess that it's counting each me as a new person each time I do it, even though I'm connecting from the same IP with the same exact browser configuration.