sexual tension?

Recently in a yahoogroup I'm part of, a discussion was started as to what works for sexual tension in a romance. It got me to thinking. Some authors are experts at creating sexual tenion without the actual act taking place. Some stories seem to fall short on the tension but have tons of sex. That doesn't work for me. I want the tension and I want it to mean more than just sex. But I still haven't been able to come up with an exact reason some stories work better than others in the sexual tension aspect. It's something I believe I'll have to think on more. But I'd like to know what you all think makes a story's sexual tension work. Are there things authors do or don't do that make things work better than others? Are some stories trying too hard to be sexy and fall short? What book you think of as the best for sexual tension, with or without the acutal act taking place?

hugs until later,
WendyK