Very rarely, but it does happen! Usually mice, those cute little things. They can be a friendly bunch - not surprising, since they lack the advantages of size and strength that let brutes be the aggressive assholes they are. Enjoyable company. I even stayed at a small village of 'em once, though I had to make camp close by since their structures were... well, not suited for one my size, so to speak.

And yeah, you can have fun with small mice, in ways you can probably already imagine! And there were a few that were adventurous enough to try, perhaps inspired by the rare visit of a larger creature that wasn't out to eat them or ruin their hometown.