Yesterday we got into a discussion about Pluto (the Dwarf Planet) and inevitably someone claimed "Pluto is still a planet to me!" I responded that since we've only know about Pluto for 87 years – 1/3rd of it's "alleged" orbit of 248 years, and it has an off-kilter (17 deg), elliptical orbit, that maybe it wasn't any kind of planet but rather just an random cluster of space rocks that have an orbit more akin to Haley's Comet.
Of course this was just wild speculation to point out how un-planet like Pluto really is. What I found interesting was the lack of easy access to how Pluto's orbit was determined.
I'm still looking but here's a couple of sites with basic info on the Dwarf Planet.