I would be interested, but you maybe could be a little more specific. Is this going to be an IM scene? What 'part' would you want me to play? When would be a good time? Are we even in the same time zone?
A few more details might help. I saw this thread when you first posted, but I did not respond because I have no idea what exactly you are looking for. Also, how long would you be expecting the IM session to last? Which medium are you using, AIM or MSNIM, or another server? I have two babies, I can't be on too long, they need my attention too. Perhaps if you could describe your fantasy a little more fully, any interested subs might have a better idea what you're looking for. If I wouldn't suit your purposes, another might, if you're patient.
If you're expecting an immediate response, perhaps you could try a chatroom; (MSN has some in the 'Lifestyles' category, and I would assume AOL has something similar) where you can wander in and state your fantasy, and perhaps subs will respond immediately. Or you might need a little patience. Especially if you look for a sub to participate here. Many of the participants here don't check the page every day, maybe once a week or so, and expecting a fast response to a post is a little unrealistic.
If you describe the fantasy in a little more detail, I might participate. I'll keep an eye on your thread.