Aside from my tuner, that I don't class as an effects pedal, I have a distortion pedal, a chorus and an octaver. I find that I use them mostly when we are obliged to play covers so that we can replicate the sound of the original e.g. Muse - My Time Is Running Out, Nirvana - Come As You Are.
For our original material they get infrequent use - a bit of chorus and octave mostly.