If this thread seems familiar, it's probably because I posted it in non-forum roleplay earlier. Because I'm quite keen on trying it out, however, I figured I'd open it up to a wider audience.
It's a fairly simple concept: A pair of siblings ( or at least one of them ) trades places, as it were. A minimum would be a degree of play with crossdressing, but it can go further - as far as we decide we want to, really. The siblings can be either a brother and a sister, or two sisters. In either case, I would prefer to play one of the sisters. An element of bondage and domination would be a welcome addition, too.
If this sounds like your cup of tea, feel free to take a look at my O/Os, and let me know through a PM. I'm also available on YIM, details in my profile.