I've been just leaving my icing in the bag with the coupler and sometimes even the tip on then I stick it in a ziplock with all the other left over colors and this really saves time in the long run. What do you all do? I'm talking about buttercream although I have done this with royal too.

I do the same thing. I teach Wilton classes, so I always have extra icing. I just keep my decorator bags in a ziploc on the counter. I usually take the tips off. I just put a piece of plastic wrap over the end and then put the coupler ring over the plastic to hold it on. I also put a small chip clip on the back of the decorator bag. I can keep the icing a few weeks like this. Royal Icing tends to separate faster than buttercream, so it doesn't keep quite as long.