Bells and other noise makers can be kinda fun, tho! Personally, I just kinda trundle along, and do my best to stay out of other peoples way, and if it is obvious that someone has not seen me, announce my intentions.
The organizers of RAGBRAI want everyone to have a great, safe experience, which is why they stress the ride right ideals, and try and discourage pace lines. However, personally, I have never felt threatened by the go-fast folks....they are just out there doing thier ride, and I do mine, and we all seem to get along great.