Clips Nation, a Los Angeles Clippers community

When it comes to rivalries, for the Clippers there is really only one team: sharing a city and an arena with the Lakers makes them a geographic rival, and for the time being at least it looks like a good competitive rivalry as well.

Do the Clippers have any team that would qualify as a rival in the Eastern Conference?

What is the true nature of rivalry? Who is the Clippers biggest rival? There's an obvious answer, but are there other answers as well?