Yeah,
I could probably find use for such a thing too. It would be cool, I don't know if there are any things hindering such a thing from being made or not. Whoever made it would have to pay royalties to Apple for using the 30-pin connector in their device, so that might deter some lower end companies from making it. But I would honestly think that something like this would have been made already in the years that the iPad has been on the market. It's such a simple idea and could be generally practical for a decent amount of tasks. I would buy one if I someone started making them. But unless I'm just unaware there isn't anyone making them right now. I have looked at almost every type of iPad accessory on the market right now and have never come across something like this.
My only suggestion is to search for "dual 30-pin connector" and similar phrases to see if you can't find a lead in some search result. That would probably be your best bet if there is already something like this out there.
