Here's a little interesting trivia for you. While you might think the name Banjo-Kazooie to be completely made up, turns out it's actually at least partially inspired by a real-life person!
Andy Robinson over at VGC let loose with some information he gleaned while talking to various game devs in Japan. Former Nintendo president Hiroshi Yamauchi's grandson is named Banjo Yamauchi, and his son has the name Katsuhito Yamauchi. Put the two together and you get Banjo-Katsuhi.
When former RARE deg Gregg Mayles was asked about this being true, he confirmed that the Banjo half indeed was, but he was unsure about the Kazooie side. I think with the Banjo part being true, the Kazooie/Katsuhi connection makes a lot of sense. Still, it's just amazing that there's someone out there named Banjo!