Six frames, six different SSR designs.
I try and be simple when making SSRs. If you count the mounting piece I don't go higher than four pieces when making them.
This is meant to resemble a shoulder-fired, vertical-launch missile. It might blend in a little to the frame it's mounted to though.
Another like the previous. It stands out from the frame though.
This is the one I'm most proud of. I took an essentially useless minifig accessory and turned it into something that is recognizable as a SSR.
So there you go. Six different designs, all pretty simple in execution.