Probably a bit late to answer this at this point, but I'm going to anyway.
Depends on your setup, how many flashes, what models, what camera, etc.
I have 2 yongnou 600EX's myself and this will let you do off camera rear curtain sync. Rather than trying to tether the flashes together, or do something odd, I put one on the camera in ETTL or M (depending on your preference) and turn on rear curtain sync. The second flash is off camera and set to be an optical slave. The YN600EX has two optical slave modes, one for ETTL that ignores the pre-flash, and one that will just fire normally, so set it as appropriate to match the on-camera flash mode.
This should basically use the rear curtain sync of the on camera flash to trigger any additional flashes. That setup only uses 2, but you could add more quite simply. The one downside is that the flashes need line of sight. It would be great if there was a radio mode for this but there doesn't appear to be.
(Another option is to use your cameras built in pop-up flash as the trigger flash in place of having one on the camera. Again, depends on what camera model you specifically have, but many prosumer level bodies will let you adjust how the pop up flash fires, what power it uses, is it rear curtain or not, etc. I'd set it to more or less the lowest power so that it can trigger the other flashes but won't really affect your photo)