The ADL compiled an interesting list of right-wing conspiracies and attacks here:
http://www.adl.org/assets/pdf/combating-hate/Right-Wing-Plots-Acts-Conspiracies-1995-2015.pdf
Most of them are just loner nuts, but there are enough true conspiracies to worry those of us with respect for the law and Constitution.
I just got to the second one that list. I remember the story about Chevie Kehoe killing the gun dealer and family. Although it was true that Kehoe could be considered anti-gov’t nut, this crime was murder with robbery as a motive, not domestic anti-gov’t terrorism as is described in ADL.