The title contains most of the relevant information of this question, I think.
Some years ago, I read a short story, I think by the sf writer Greg Egan. It is set possibly in the far future, when an intelligent computer on the outskirts of the solar system senses an electronic wavefront travelling outward from Earth which identifies itself as Marco Polo, and has a conversation with it, as it/he leaves the solar system. The plot is sufficiently unlikely even for a sf story that perhaps it would be better described as science fantasy.
I wanted to read it again, but it is difficult to look for it without a title. To my surprise, Google seems unable to identify this story. Also I don't recognize the story from the titles at Greg Egan's own Bibliography, so maybe I am wrong about the author, though it does seem like the kind of story Egan would write.
I don't recall many other details. I think there is a sequence where Polo recalls his travels, possibly in China. It doesn't seem like the sort of plot that could easily be confused with another story, and I suspect if someone has read it they will remember it. Thanks in advance.
UPDATE: Thanks to beichst for this (difficult) identification. This story has not been much reprinted, but I see that I read this in The Arbor House Treasury of Science Fiction Masterpieces, which I think I borrowed from the Chapel Hill Public Library. I see they have it in their catalog. Isn't the internet handy?