You could. Yeyinde is working on rsc system that he will hopefully add an encryption to the system. I am going to have to throw some money at that lazy Predator to get it done though...
I haven't tried, but you could also try creating a .rb file and ecrypting that. You could create your script in say a text document, then read the text document, encrypt each string, and dup them into a .rb file.
I will try and make a simple script for this, since I never even thought of it before.