What might silicone-based life look like?

I usually see silicon-based life portrayed as being crystalline in nature. I've read that silicone-based life is perhaps more plausible, but I've never seen an artistic portrayal; the only thing I know about their appearance is that they apparently probably *wouldn't* look the way silicon-based life looks in the art. So what would it be likely to look like? How would it be different in appearance from organic life? Would there be any visible features which we would see as especially weird or which would scream "I'm silicone-based, not organic!"?

Also, this is for science-fictional purposes, so answers along the lines of "there is no evidence that non-organic life exists" aren't going to be terribly helpful. Thanks!