There are actually quite a few without lead-in radials.... Humboldt, Tennessee (M53) doesn't have one, nor does the VOR rwy 23L at Knoxville/McGHee-Tyson (KTYS). I've seen alot more, but those are the only ones I can remember off the top of my head.
Speaking of crazy arcs....anybody here ever flown into the Martin State Airport in Baltimore (KMTN)?? It's kinda wild....there's a VOR approach that has the final approach course along a DME arc....FUNKY!!!!