Cardiff have a team , they're called the Cardiff Demons RLFC, my mate plays for them. There was the Blue Dragons based at the football club here 20+ years ago that Im sure could have gone far with the same structure we are putting in place in Bridgend now.
I think we have a certain rapport with our other non heartland clubs at Harlequins especially when we went up to Twickenham earlier in the season and Catalans. We have an understanding and a certain level of support from them as we share a common link in trying to grow RL's popularity outside the north of England and the challlenges we all face.
Thats not particularly a rivalry in the sense of Hull / KR or St Helens /Wigan but we still want to compete with them on and off the field.
Salford last year beating us to everything was about the closest we've been to a real tense rivalry. The RU rivalries down here get the passion going for most people and I think we would well do with that here in RL to get people passionate about their club.. Though if there was suddenly a professional Cardiff club , ,I'd find that very awkward.