I'm working on a lead vocal track at the moment and I've started in this order:
1- Pro Channel PC2A Leveller
2- FX bin: FabFilter ProEQ
3- FX bin: epicVerb
 
Then I started wondering.  I know rules are there to be broken in the interest of getting the sound you're happy with, but I just wondered if there are some rules of thumb and/or some no-no's when it comes to FX order.
 

IMO, I think it all comes down to preference and what sounds best to your ears at the end of the day. One technique I've started using sometimes is cutting eq before compression and boosting after. Picked it up from watching a video from Dave Pensado a while back.