This pisses me off every fucking time I see it.
If you are genuinely short of characters couldn't you at least use capitals?
Otherwise there is no excuse for 'rip'.
It's lazy, callous and insensitive.
'rip' what the fuck does it mean? All it says to me is I can't be arsed to think of anything appropriate so this will do and I can't actually be arsed enough to use capitals.
If you want to say 'rest in peace' just bloody type it in full!
Or better still, think of what you actually feel and want to say rather than some shitty, meaningless pacifier.
Can you tell I fucking hate 'rip'?
And breathe...